As a bug type user, i would like to give my slightly biased thoughts on genesect. While I may not be the best bug user in the world, i believe my skill with the type is prominent enough that my thoughts on the poke should not be automatically discarded. With that said, onto the matter at hand.
Genesect
I have a hard time deciding if genesect is broken or not. On one hand it gets extremely good coverage, especially against types that are otherwise problematic to bug, especially flying. While one could make an argument that genesect with douse drive could punch holes into fire teams as well (and it certainly can in the perfect circumstances) with the help of sticky web, in reality the matchup hardly ever goes well enough for this situation to arise, mainly due to the fact that fire always runs charizard, whose both mega forms halve the damge water does to them (and others for chari-y), while also being guaranteed a ohko onto genesect, while being faster than it because it's not running scarf. While charizard (and fire teams as a whole) are weak to stealth rock, setting up multiple hazards against pokemon that are all pretty much guaranteed to 2hko in the best case scenario is an incredibly hard stunt to pull, and if you manage that then you really aren't winning due to genesect, but being able to outplay the opposing player. While douse drive can occasionally win you a game against fire, i believe it is inferior to the other prominent sets it runs, mainly the physical banded/shiftgear and scarfed special variants, due to it's unreliability of doing heavy damage. Regardless, charizard-x for example, has (barring sturdy and sash, but fire uses rocks too) 3 pokemon that don't get OHKO to worry about on a bug team after +1 DDance - a fully defense and hp invested armaldo (who still dies if rocks are up and can't OHKO back regardless), crustle, who has the same issue as armaldo, and shuckle (lol). Everything else is either too frail or simply not viable in the current metagame due to largely inferior stats (such as masquerain). Regardless, fire beating bug is nothing new and should not be the main focus of this post.
I will go into detail on how good genesect is against each other matchup as well, as i have battled each one (except poison, so that will be purely speculation) a couple of times or more.
Normal
Against a normal team, genesect behaves similarly to scizor, in while it can't really sweep without setting up, due to it's typing it's pretty hard to kill, as normal usually doesn't run more than one fire move, if even that. Then again, seeing (as previously mentioned), that all the additions to the monotype roster are weak to fire, i believe smarter players have incremented at least some fire moves onto their team. as for the matchup itself, there are not a lot of pokemon normal has that can stand toe to toe with genesect. Normal's first priority when dealing with genesect would be to figure out it's set, making a guess based on the lineup and then using what walls they have on their team to confirm, or use ditto if genesect carries a fire move and no scarf. It is hard for a normal team to be prepared for all of genesect's sets while still being viable to use against every other type, so with that in mind, normal has a genuine disadvantage against bug with genesect. However, since bug teams have a tendency to run mons with incredibly strong close combats (be it pinsir or heracross, or even superpower scizor), i have so far been under the impression that bug has an advantage regardless, genesect just makes the fight even harder.
Water
Since there are a few different water team types, I'll go into each one in short. The SS teams see little threat in genesect due to being generally faster, scarfed gene or otherwise, and the frailty of the pokemon, while having no resistance to water. Since Damp rock has been banned, the strength of SS has been toned down quite a bit and the matchup is as skill (and luck) based as ever, and genesect has a small impact to this due to its coverage moves. Genesect shines much more against balanced water and water stall, although mainly if it's specially inclined, as it has access to both thunderbolt and energy ball, meaning that it can hit moderately hard against most of the pokes used on these teams. However, this fight is more prediction based, as it pretty much requires you to guess right whenever using genesect to not have it severely crippled or even die, and while u-turn spamming is definitely an option, there are practically no bug pokemon that can easily take stab water attacks, especially the SpA kind, and the general bulk of a large amount of water pokemon make them very difficult to wear down using this tactic. Overall, I would say that genesect improves the matchup for bug's side, but not by much.
Electric
Genesect doesn't have much of an impact against electric types, due to the fact that it doesn't really get any particularly useful coverage against electric teams, and while fast, remains to be outsped by quite a few dangerous pokemon on electric's side, the biggest offender here being mega-manectric. Moreover, sticky web is a smaller boon against electric due to both sides having access to it. The banded extremespeed set is the most useful here, but genesect does not particularly shine in this matchup.
Grass
The unbans were a mixed bag for the bug vs grass matchup. While bug got genesect, grass now has skymin, which is both faster and able to ohko it, as well as many other threats that bug could use against it. Due to seed flare, not many things can really deal with skymin on bug's side, especially since it is also immune to sticky web, while the matchup is not unbeatable for bug, especially due to strong priority moves from scizor and pinsir-mega, the new unbans definitely gave grass a bigger advantage. when only looking at genesect, mega venusaur can wall it quite effectively, especially if it runs earthquake, but obviously has problems against the previously mentioned mega pinsir, which frankly pretty much destroys grass as a whole.
Ice
This matchup is definitely in genesect's forte. with access to a powerful stab steel move on both attacking spectrums, this is basically a type that gene can actually sweep. However it is not as easy as it may seem on first look due to the newly unbanned kyu-w, which is faster and can guarantee an OHKO on gene, given the chance. The key to this matchup for both sides is obviously hazards, although bug comes out better from this due to the power of sticky web, as most of viable ice mons are grounded. With that being said, genesect shines little in this matchup, due to being outclassed by a certain priority steel type user, who becomes practically impossible to stop for ice, while only requiring rocks to be set up. While genesect is incredibly strong in this matchup, it's just an overkill poke, as ice has a lot of trouble beating bug anyway, due to the sheer a mount of pokes that run strong super effective moves against it.
Fighting
Mainly due to the existence of mega medicham, and to a lesser extent, hawlucha and sash nape, genesect shines little in this matchup. sticky web is crucial for bug, but due to a vide variety of pokes resisting whatever coverage gene has, it truly becomes a game of predicts, very similarly to water. What makes the matchup differ is that fighting pokes tend to have a lot of better super effective coverage than water's usual neutral or super effective stab. the biggest use of genesect here is killing off keldeo if possible and using u-turn to create momentum, although you could argue that galvantula actually does this job better, despite being even more frail.
Poison
In this matchup, genesect's main strength would be in dealing with nidos using icebeam and using it's strong stab steel moves against everything else. the matchup is kinda similar to grass, in a sense that pinsir mega can ruin a poison teams day quite hard, should it be running earthquake, and crobat could be seen as a significantly less problematic skymin. I have yet to see a poison team after the ladder restart on either main or frost server though.
Ground
Ground has always been a tricky matchup for bug, due to excadrill and garchomp being able to mandhandle volcarona and being somewhat lacking on ice, water and grass coverage. While some mons may run hp ice or giga drain, it was generally never enough to sweep ground due to it being able to somewhat resist all 3 types and kill the usually frail user of these moves in retaliation. With the addition of genesect, the matchup has changed, but not by much. Genesect has the ability to OHKO excadrill, although only if it uses blaze kick over flamethrower with Atk investment. However, this could be potentially huge for bug, as it, the landoruses and garchomp (which die to ice anything, conveniently), are the only things keeping volcarona in check from wreaking havoc on ground teams, especially if it runs giga drain. However, as is the case with most of the stronger types (and ground definitely is one of those), the fight is still very hard due to hazard setters being weak to either rock or 4x fire and sand rush exca killing everything ever with lorb stab earthquake.
Flying
Ah yes, the "after rocks genesect rapes anything with wings argument". I honestly believe that, while strong against flying, genesect's strength in the matchup is overrated, simply because bug never had good ice coverage before, and that has thrown flying users off guard, as it's an attack type they didn't need to prepare for from a type they usually have a clear advantage over. In reality, due to flying usually running one of the charizard megas, and with the bulky defenses of skarmory and zapdos, who sometimes both run defog, it is hard for bug to keep hazards up, while surviving the usually lethal attacks from the fliers, and having to deal with rocks themselves. While genesect really helps with the matchup due to triple beam coverage for example, it does not turn the mapside upside down into heavily bug favor simply because of that. As usual, the matchup relies heavily on predicting skills from both sides.
Psychic
I must admit, the new generic bug makes fighting the old generic psychic a joke. Genesect's fast u-turn, especially after an attack boost, makes some serious dents to whatever poke will be taking the hit, and there is very little that the usual mew, meloetta, slowbro, mega medi/mega garde, metagross, Lati@s psychic can do about it due to usually being outsped. However, should psychic implement scarf victini, surprise with scarf latios or even flamethrower slowbro, it can seriously make the bug user rethink the tactic of "hurrturn to win". Of course, you have to be able to deal with webs as a psychic user, but this has always been the case in this matchup, especially due to the usual bug team running about 4-5 pokes that can seriously hurt psychic pokes. Saying that gene can singlehandedly sweep psychic is flat out-wrong as it definitely has answers, they fight is just more difficult, albeit maybe more predictable for the psychic user (which is a good thing, no?)
Bug
Bug vs Bug is still volcarona and hazards centered, and the value of pinsir has lessent a bit due to an extra poke being able to deal with it, but other than that, the matchup has changed suprisingly little, especially since both sides will always have genesect and volcarona.
Rock
While rock has the similar problem that ice does in the form that, the steel bugs wreck a lot oh shit, rock has clear answer to them in two megas - aggron, and to a lesser extent, tyranitar running fire punch. While aggron isn't an ideal pokemon to run and tyranitar cannot take the hit as strong as aggron, they are both quite capable of not only killing genesect and scizor, but the rest of bug as well. rock has the problem with being generally slow, but besides genesect and heracross there are not that many pokemon that are fast and need to be watched out for. While genesect is a problem for rock, the type has a healthy amount of pokemon that can cripple it's sweeping potential (which it undeniably has), I've even seen fire fang aerodactyl more than once these last few days. The hardest set to deal with is most certainly the shift gear one, as it makes iron head truly a monstrous murder weapon, which pretty much only mega aggron can stop.
Ghost
I have to say that ghost is the most interesting matchup for me. It's pretty hard to predict, as most viable ghosts run different items and sets. Prediction however, serves as a large part of playing with genesect, so his value in this matchup is a bit diminished, especially since it doesn't have any particularly useful moves against ghosts (if one poke takes super effective damage from something, the other is immune or resists it), and u-turn itself is resisted.the choiced sets are for this reason the weakest, but quite a few ghosts are faster than it nad can deal quite heavy damage, therefore making genesect a rather mediocre pokemon in this matchup. On a side note, I seriously believe that ghost deserved getting aegislash back and it should not be banned again, as it seems to give ghost that extra "oomph" it was previously lacking.
Dragon
Hallelujah ice coverage! The thing bug missed the most was quite the disability before in this matchup, but now that it's fixed... it's still a difficult matchup. Dragon has a huge variety of pokemon some of which even deal with genesect quite well. As the threats are quite varied, bug generally needs to set up both rocks and web to be able to really deal with the sheer number of threats, and as previously mentioned, setting up multiple hazards is hardly ever easy. Not only that, but even with both hazards set, gene is still unable to deal with quite a few threats that dragon has, although if it's scarfed the list is basically scarfed levitating/flying dragons, most of which carry fire coverage. That being said, genesect is still amazing in this matchup, as very few things can manage to survive a download boosted ice beam and OHKO it back.
Dark
Dark is a trickier matchup for bug than most people seem to believe. Relying on sticky web is extremely dodgy, due to bisharp and bug not resisting sucker punch, but without the slowdown it's difficult to deal with some of the threats, most notably greninja, as bug doesn't really have any pokes that enjoy facetanking a life orb boosted hydro pump, while tyranitar can tank just about anything that isn't close combat or superpower, and then KO whatever hit it back. Dark however, has access to sableye for that any other Atk based threats, and, when combined with mandibuzz, ensure that dark's weaknesses are generally well covered. Saying that gene can handily beat dark with just u-turning is flat out wrong, because while it definitely helps, even dealing really good damage against some threats, it can be either healed off by the mandis and sables and flat out OHKOd by a +2 bisharp should it get the chance for a boost. A special variant of genesect with bug buzz would certainly do more damage, but has issues with tyranitar. Make no mistake though, even if gene can't outright deal with certain dark pokemon, he may be able to cripple them quite well, for other threats such as volcarona or heracross to finish off.
Steel
Before aegislash was banned, bug vs steel was the most infuriatingly difficult matchup for me. Unlike fire, which was basically "lose if you predict wrong once", steel you would lose to if you didn't run a specific set, unless your opponent misplays or you get lucky. While the matchup is still heavily prediction based, the banning of aegi from steel and now the unbanning of genesect have definitely made the matchup more managable, as bug now has an extra fire user who can do some serious damage, if not kill dangerous steel pokes who volcarona couldn't deal with, and mega heracross is more appealing, as throwing a close combat means that something is going to die, even if that something is a skarmory switching in. While steel also has access to genesect, it gets less value on its side of the matchup, as bug teams tend to run pokes that can take non-stab fire moves, with the exceptions of the bug/steel combination.
Fairy
The biggest problem for bug in this matchup is not mega mawile, although it certainly is a threat. The actual troublecausers would be the prankster twavers, klefki and whimsicott. Bug relies most on it's speed to deal with its matchups, and being paralized on priority is definitely the strongest counter to it, especially since bug doesn't run healbell/aromatherapy. While genesect, like scizor, can easily deal with most threats on a fairy team, even moreso with it's fire and electric coverage, it is also significantly worse off paralized, due to only having access to extremespeed as priority, and being much more frail. Naturally, it can deal great amounts of damage to a fairy team with it's steelstab of choice, but expecting a steel pokemon not to do too much damage to fairy is a bit dumb. in general, with or without a steel move, it is certainly an useful mon in this matchup, but not as good as scizor.
Note that genesect, like any other pokemon, only has access to 4 moveslots and one item, and therefore can't have a moveset that would get the best out of it in any matchup, and while some sets are definitely really good against certain matchups, they are mediocre or weak against others, and a different poke could serve better in that matchup than genesect. I honestly believe that the strongest bug pokemon available in monotype remains volcarona, as it has incredible stats and decent coverage for what it's meant to do - be a late game sweeper, while resisting the most dangerous of bug's weaknesses.
Genesect should not be considered a sweeper, rather, it is an incredibly effective offensive pivot, one that bug has no effective alternative for, as ice coverage on viable pokemon is limited to hidden power ice, which is simply too weak to use unless the target has a 4x weakness to it, or it's the only really damaging option (such as against thundy-t, gliscor, landoruses), due to most rock attack users being slower than defensive roosting fliers, or in thundurus' case, being volt switched into skarmory to tank it with no problems.
That's pretty much all that comes to mind right now that I wanted to say about genesect. I would understand if the overall opinion would be to reban genesect, as i can see how it cause serious problems in some matchups. However, reading what has been posted so far, it seems to me that most people have (understandably) incredibly biased views on gene being too OP for the monotype meta. That, and the people posting replays of genesect "singlehandedly" winning a game should be more observant on whether the opposing team of the genesect user (or any of the ubers released, for that matter) made some misplays that led to the defeat in which the unbanned poke played a part in, think what they could have done better and if the situation was inevitable. Some of these really seem to be played against inexperienced players.
Genesect
I have a hard time deciding if genesect is broken or not. On one hand it gets extremely good coverage, especially against types that are otherwise problematic to bug, especially flying. While one could make an argument that genesect with douse drive could punch holes into fire teams as well (and it certainly can in the perfect circumstances) with the help of sticky web, in reality the matchup hardly ever goes well enough for this situation to arise, mainly due to the fact that fire always runs charizard, whose both mega forms halve the damge water does to them (and others for chari-y), while also being guaranteed a ohko onto genesect, while being faster than it because it's not running scarf. While charizard (and fire teams as a whole) are weak to stealth rock, setting up multiple hazards against pokemon that are all pretty much guaranteed to 2hko in the best case scenario is an incredibly hard stunt to pull, and if you manage that then you really aren't winning due to genesect, but being able to outplay the opposing player. While douse drive can occasionally win you a game against fire, i believe it is inferior to the other prominent sets it runs, mainly the physical banded/shiftgear and scarfed special variants, due to it's unreliability of doing heavy damage. Regardless, charizard-x for example, has (barring sturdy and sash, but fire uses rocks too) 3 pokemon that don't get OHKO to worry about on a bug team after +1 DDance - a fully defense and hp invested armaldo (who still dies if rocks are up and can't OHKO back regardless), crustle, who has the same issue as armaldo, and shuckle (lol). Everything else is either too frail or simply not viable in the current metagame due to largely inferior stats (such as masquerain). Regardless, fire beating bug is nothing new and should not be the main focus of this post.
I will go into detail on how good genesect is against each other matchup as well, as i have battled each one (except poison, so that will be purely speculation) a couple of times or more.
Normal
Against a normal team, genesect behaves similarly to scizor, in while it can't really sweep without setting up, due to it's typing it's pretty hard to kill, as normal usually doesn't run more than one fire move, if even that. Then again, seeing (as previously mentioned), that all the additions to the monotype roster are weak to fire, i believe smarter players have incremented at least some fire moves onto their team. as for the matchup itself, there are not a lot of pokemon normal has that can stand toe to toe with genesect. Normal's first priority when dealing with genesect would be to figure out it's set, making a guess based on the lineup and then using what walls they have on their team to confirm, or use ditto if genesect carries a fire move and no scarf. It is hard for a normal team to be prepared for all of genesect's sets while still being viable to use against every other type, so with that in mind, normal has a genuine disadvantage against bug with genesect. However, since bug teams have a tendency to run mons with incredibly strong close combats (be it pinsir or heracross, or even superpower scizor), i have so far been under the impression that bug has an advantage regardless, genesect just makes the fight even harder.
Water
Since there are a few different water team types, I'll go into each one in short. The SS teams see little threat in genesect due to being generally faster, scarfed gene or otherwise, and the frailty of the pokemon, while having no resistance to water. Since Damp rock has been banned, the strength of SS has been toned down quite a bit and the matchup is as skill (and luck) based as ever, and genesect has a small impact to this due to its coverage moves. Genesect shines much more against balanced water and water stall, although mainly if it's specially inclined, as it has access to both thunderbolt and energy ball, meaning that it can hit moderately hard against most of the pokes used on these teams. However, this fight is more prediction based, as it pretty much requires you to guess right whenever using genesect to not have it severely crippled or even die, and while u-turn spamming is definitely an option, there are practically no bug pokemon that can easily take stab water attacks, especially the SpA kind, and the general bulk of a large amount of water pokemon make them very difficult to wear down using this tactic. Overall, I would say that genesect improves the matchup for bug's side, but not by much.
Electric
Genesect doesn't have much of an impact against electric types, due to the fact that it doesn't really get any particularly useful coverage against electric teams, and while fast, remains to be outsped by quite a few dangerous pokemon on electric's side, the biggest offender here being mega-manectric. Moreover, sticky web is a smaller boon against electric due to both sides having access to it. The banded extremespeed set is the most useful here, but genesect does not particularly shine in this matchup.
Grass
The unbans were a mixed bag for the bug vs grass matchup. While bug got genesect, grass now has skymin, which is both faster and able to ohko it, as well as many other threats that bug could use against it. Due to seed flare, not many things can really deal with skymin on bug's side, especially since it is also immune to sticky web, while the matchup is not unbeatable for bug, especially due to strong priority moves from scizor and pinsir-mega, the new unbans definitely gave grass a bigger advantage. when only looking at genesect, mega venusaur can wall it quite effectively, especially if it runs earthquake, but obviously has problems against the previously mentioned mega pinsir, which frankly pretty much destroys grass as a whole.
Ice
This matchup is definitely in genesect's forte. with access to a powerful stab steel move on both attacking spectrums, this is basically a type that gene can actually sweep. However it is not as easy as it may seem on first look due to the newly unbanned kyu-w, which is faster and can guarantee an OHKO on gene, given the chance. The key to this matchup for both sides is obviously hazards, although bug comes out better from this due to the power of sticky web, as most of viable ice mons are grounded. With that being said, genesect shines little in this matchup, due to being outclassed by a certain priority steel type user, who becomes practically impossible to stop for ice, while only requiring rocks to be set up. While genesect is incredibly strong in this matchup, it's just an overkill poke, as ice has a lot of trouble beating bug anyway, due to the sheer a mount of pokes that run strong super effective moves against it.
Fighting
Mainly due to the existence of mega medicham, and to a lesser extent, hawlucha and sash nape, genesect shines little in this matchup. sticky web is crucial for bug, but due to a vide variety of pokes resisting whatever coverage gene has, it truly becomes a game of predicts, very similarly to water. What makes the matchup differ is that fighting pokes tend to have a lot of better super effective coverage than water's usual neutral or super effective stab. the biggest use of genesect here is killing off keldeo if possible and using u-turn to create momentum, although you could argue that galvantula actually does this job better, despite being even more frail.
Poison
In this matchup, genesect's main strength would be in dealing with nidos using icebeam and using it's strong stab steel moves against everything else. the matchup is kinda similar to grass, in a sense that pinsir mega can ruin a poison teams day quite hard, should it be running earthquake, and crobat could be seen as a significantly less problematic skymin. I have yet to see a poison team after the ladder restart on either main or frost server though.
Ground
Ground has always been a tricky matchup for bug, due to excadrill and garchomp being able to mandhandle volcarona and being somewhat lacking on ice, water and grass coverage. While some mons may run hp ice or giga drain, it was generally never enough to sweep ground due to it being able to somewhat resist all 3 types and kill the usually frail user of these moves in retaliation. With the addition of genesect, the matchup has changed, but not by much. Genesect has the ability to OHKO excadrill, although only if it uses blaze kick over flamethrower with Atk investment. However, this could be potentially huge for bug, as it, the landoruses and garchomp (which die to ice anything, conveniently), are the only things keeping volcarona in check from wreaking havoc on ground teams, especially if it runs giga drain. However, as is the case with most of the stronger types (and ground definitely is one of those), the fight is still very hard due to hazard setters being weak to either rock or 4x fire and sand rush exca killing everything ever with lorb stab earthquake.
Flying
Ah yes, the "after rocks genesect rapes anything with wings argument". I honestly believe that, while strong against flying, genesect's strength in the matchup is overrated, simply because bug never had good ice coverage before, and that has thrown flying users off guard, as it's an attack type they didn't need to prepare for from a type they usually have a clear advantage over. In reality, due to flying usually running one of the charizard megas, and with the bulky defenses of skarmory and zapdos, who sometimes both run defog, it is hard for bug to keep hazards up, while surviving the usually lethal attacks from the fliers, and having to deal with rocks themselves. While genesect really helps with the matchup due to triple beam coverage for example, it does not turn the mapside upside down into heavily bug favor simply because of that. As usual, the matchup relies heavily on predicting skills from both sides.
Psychic
I must admit, the new generic bug makes fighting the old generic psychic a joke. Genesect's fast u-turn, especially after an attack boost, makes some serious dents to whatever poke will be taking the hit, and there is very little that the usual mew, meloetta, slowbro, mega medi/mega garde, metagross, Lati@s psychic can do about it due to usually being outsped. However, should psychic implement scarf victini, surprise with scarf latios or even flamethrower slowbro, it can seriously make the bug user rethink the tactic of "hurrturn to win". Of course, you have to be able to deal with webs as a psychic user, but this has always been the case in this matchup, especially due to the usual bug team running about 4-5 pokes that can seriously hurt psychic pokes. Saying that gene can singlehandedly sweep psychic is flat out-wrong as it definitely has answers, they fight is just more difficult, albeit maybe more predictable for the psychic user (which is a good thing, no?)
Bug
Bug vs Bug is still volcarona and hazards centered, and the value of pinsir has lessent a bit due to an extra poke being able to deal with it, but other than that, the matchup has changed suprisingly little, especially since both sides will always have genesect and volcarona.
Rock
While rock has the similar problem that ice does in the form that, the steel bugs wreck a lot oh shit, rock has clear answer to them in two megas - aggron, and to a lesser extent, tyranitar running fire punch. While aggron isn't an ideal pokemon to run and tyranitar cannot take the hit as strong as aggron, they are both quite capable of not only killing genesect and scizor, but the rest of bug as well. rock has the problem with being generally slow, but besides genesect and heracross there are not that many pokemon that are fast and need to be watched out for. While genesect is a problem for rock, the type has a healthy amount of pokemon that can cripple it's sweeping potential (which it undeniably has), I've even seen fire fang aerodactyl more than once these last few days. The hardest set to deal with is most certainly the shift gear one, as it makes iron head truly a monstrous murder weapon, which pretty much only mega aggron can stop.
Ghost
I have to say that ghost is the most interesting matchup for me. It's pretty hard to predict, as most viable ghosts run different items and sets. Prediction however, serves as a large part of playing with genesect, so his value in this matchup is a bit diminished, especially since it doesn't have any particularly useful moves against ghosts (if one poke takes super effective damage from something, the other is immune or resists it), and u-turn itself is resisted.the choiced sets are for this reason the weakest, but quite a few ghosts are faster than it nad can deal quite heavy damage, therefore making genesect a rather mediocre pokemon in this matchup. On a side note, I seriously believe that ghost deserved getting aegislash back and it should not be banned again, as it seems to give ghost that extra "oomph" it was previously lacking.
Dragon
Hallelujah ice coverage! The thing bug missed the most was quite the disability before in this matchup, but now that it's fixed... it's still a difficult matchup. Dragon has a huge variety of pokemon some of which even deal with genesect quite well. As the threats are quite varied, bug generally needs to set up both rocks and web to be able to really deal with the sheer number of threats, and as previously mentioned, setting up multiple hazards is hardly ever easy. Not only that, but even with both hazards set, gene is still unable to deal with quite a few threats that dragon has, although if it's scarfed the list is basically scarfed levitating/flying dragons, most of which carry fire coverage. That being said, genesect is still amazing in this matchup, as very few things can manage to survive a download boosted ice beam and OHKO it back.
Dark
Dark is a trickier matchup for bug than most people seem to believe. Relying on sticky web is extremely dodgy, due to bisharp and bug not resisting sucker punch, but without the slowdown it's difficult to deal with some of the threats, most notably greninja, as bug doesn't really have any pokes that enjoy facetanking a life orb boosted hydro pump, while tyranitar can tank just about anything that isn't close combat or superpower, and then KO whatever hit it back. Dark however, has access to sableye for that any other Atk based threats, and, when combined with mandibuzz, ensure that dark's weaknesses are generally well covered. Saying that gene can handily beat dark with just u-turning is flat out wrong, because while it definitely helps, even dealing really good damage against some threats, it can be either healed off by the mandis and sables and flat out OHKOd by a +2 bisharp should it get the chance for a boost. A special variant of genesect with bug buzz would certainly do more damage, but has issues with tyranitar. Make no mistake though, even if gene can't outright deal with certain dark pokemon, he may be able to cripple them quite well, for other threats such as volcarona or heracross to finish off.
Steel
Before aegislash was banned, bug vs steel was the most infuriatingly difficult matchup for me. Unlike fire, which was basically "lose if you predict wrong once", steel you would lose to if you didn't run a specific set, unless your opponent misplays or you get lucky. While the matchup is still heavily prediction based, the banning of aegi from steel and now the unbanning of genesect have definitely made the matchup more managable, as bug now has an extra fire user who can do some serious damage, if not kill dangerous steel pokes who volcarona couldn't deal with, and mega heracross is more appealing, as throwing a close combat means that something is going to die, even if that something is a skarmory switching in. While steel also has access to genesect, it gets less value on its side of the matchup, as bug teams tend to run pokes that can take non-stab fire moves, with the exceptions of the bug/steel combination.
Fairy
The biggest problem for bug in this matchup is not mega mawile, although it certainly is a threat. The actual troublecausers would be the prankster twavers, klefki and whimsicott. Bug relies most on it's speed to deal with its matchups, and being paralized on priority is definitely the strongest counter to it, especially since bug doesn't run healbell/aromatherapy. While genesect, like scizor, can easily deal with most threats on a fairy team, even moreso with it's fire and electric coverage, it is also significantly worse off paralized, due to only having access to extremespeed as priority, and being much more frail. Naturally, it can deal great amounts of damage to a fairy team with it's steelstab of choice, but expecting a steel pokemon not to do too much damage to fairy is a bit dumb. in general, with or without a steel move, it is certainly an useful mon in this matchup, but not as good as scizor.
Note that genesect, like any other pokemon, only has access to 4 moveslots and one item, and therefore can't have a moveset that would get the best out of it in any matchup, and while some sets are definitely really good against certain matchups, they are mediocre or weak against others, and a different poke could serve better in that matchup than genesect. I honestly believe that the strongest bug pokemon available in monotype remains volcarona, as it has incredible stats and decent coverage for what it's meant to do - be a late game sweeper, while resisting the most dangerous of bug's weaknesses.
Genesect should not be considered a sweeper, rather, it is an incredibly effective offensive pivot, one that bug has no effective alternative for, as ice coverage on viable pokemon is limited to hidden power ice, which is simply too weak to use unless the target has a 4x weakness to it, or it's the only really damaging option (such as against thundy-t, gliscor, landoruses), due to most rock attack users being slower than defensive roosting fliers, or in thundurus' case, being volt switched into skarmory to tank it with no problems.
That's pretty much all that comes to mind right now that I wanted to say about genesect. I would understand if the overall opinion would be to reban genesect, as i can see how it cause serious problems in some matchups. However, reading what has been posted so far, it seems to me that most people have (understandably) incredibly biased views on gene being too OP for the monotype meta. That, and the people posting replays of genesect "singlehandedly" winning a game should be more observant on whether the opposing team of the genesect user (or any of the ubers released, for that matter) made some misplays that led to the defeat in which the unbanned poke played a part in, think what they could have done better and if the situation was inevitable. Some of these really seem to be played against inexperienced players.