Teams aren't made entirely out of A-ranks,
I never said that they were-the point was to illustrate the extremely limited amount of relevant targets Dugtrio can successfully trap, which is the biggest knock on its viability. When the trapper in question doesn't trap all that much, and the Pokemon it traps aren't all that important, it's not very viable. Period.
I also don't think the focus sash set is actually all that bad when it traps and revenges Scrafty if hazards are down - which is obviously not always easy or effortless, but revenging Scrafty also isn't easy.
252 Atk Dugtrio Earthquake vs. 0 HP / 4 Def Scrafty: 105-124 (38.7 - 45.7%) -- guaranteed 3HKO after Leftovers recovery
You realize that Scrafty can Dragon Dance on Focus Sash Dugtrio again and Drain Punch all of the health back (it's really that weak), unless of course you manage to time it correctly and use Reversal at the exact moment Scrafty attacks. That requires quite a bit of guesswork, so I wouldn't describe this point as a positive, and you can pretty much forget about that terrible Sash Dugtrio set revenge killing Scrafty if it has a Chople Berry, or you know, attained even the slightest bit of prior damage, thus breaking the Sash.
The reason why Focus Sash Dugtrio isn't good is because it fails to actually kill anything with moderate bulk even if the target in question takes super effective damage from an Earthquake. Simply put, Dugtrio needs the power and the ability to switch moves from Life Orb or else it can't do its job nearly as effectively.
I kind of regret being as snappy about Camerupt, but Camerupt can't switch in on any fire type unless it's using a fire-type attack or running the specially defensive set
That's why you run bulk on it in the first place? The nice part about Mega Camerupt is that it needs no spa investment to promptly 2HKO the vast majority of the tier. Running SpA investment is more often than not, a waste.
(Jolteon, Rotom-C and Eelektross; Magneton doesn't see that much use to my knowledge)
The ability to absorb Volt Switch goes beyond simply stopping a few Pokemon-it involves stopping the momentum of VoltTurn teams as a whole, that's why a lot of successful teams tend to carry Ground-types in order to keep sap the opposing team's momentum at just the right time.
and it can't really switch in reliably on Rotom-C and can be bopped on the switch by Hp Water Jolteon
Lol yeah, because Jolteon commonly carries HP Water in a meta where Flygon exists. For Rotom-C, it depends on its set, it can swap into a Scarf Leaf Storm just fine, although yes it does get worn down.
Stealth Rock is always legit on an offensive mon and I agree with that being a viable niche somewhat. Alomomola and Phys Def Jellicent are hugely common hard stops, as is nearly any specially defensive water type (so things like Seismatoad and Gastrodon, though they're not commonly seen as spdef), SpDef Togetic (and, ugh, Golbat), and the special defensive set also has every offensive Meloetta set (except maybe sub CM just because you want your HP more), Phys Def Togetic, Eelektross (though it needs hp water or aqua tail to do anything).
Man, do even make the effort to see how much damage those Pokemon take, or do literally just list out anything that resists a Fire/Ground move as a "hard stop"?
Also, did you seriously just list Golbat as a counter to Camerupt? Golbat is 2HKOed by Fire Blast and is destroyed by Earth Power when it Roosts, that is not, in anyway, shape, or form a check and most certainly not a hard stop.
Physically defensive Togetic, which is the most optimal defensive spread, is 2HKOed after Stealth Rock and loses one-versus-one against Toxic variants anyway. All of the other Pokemon you listed are 3HKOed at worst, the ones with Recovery are forced to Recover and give up momentum when swapping in on an Earth Power and the ones without (Seismitoad, Eelektross) can't even swap in again. Those aren't "hard stops", just checks, and one of the checks you listed is actually countered by Camerupt itself (Eelektross), which would only have business running Aqua Tail for the sole purpose of beating Camerupt in the first place.
Flygon can also, often, come in on Camerupt, but is afraid of Wow and Hidden Power Ice.
Only if its the defensive set. Offensive Flygon takes 42% minimum from Fire Blast, not an optimal switch-in in the least bit.
Most of Camerupt's switch-ins are against Balance and Stall
I didn't know Houndoom, Delphox, Durant, Sneasel, and offensive Electric-types are mostly balance/stall mons. Granted, it won't switch in on every move they have perfectly, but it can come in to sponge their primary STAB(s).
but it doesn't do a whole lot against those playstyles unless the team has already been smashed to pieces with a wallbreaker, at which point a different fire type is often just as useful.
What kind of assertion is that? How can you even say that a Pokemon that 2HKOs the entire tier, and can cripple the few that aren't with Toxic, won't put in work vs a defensive build?
Camerupt's switch ins are admittedly low, but they're found on nearly every team.
What exactly switches into Camerupt on an offensive team that isn't 2HKOed by its STABs or destroyed by HP Ice?
Exploud can switch in on weak hits fine, and has very similar bulk (but slightly less so) to modest Camerupt.
Having the same bulk is irrelevant when Exploud has no resists to make use of and doesn't invest in its bulk anyway.
I fail to understand how Exploud is afraid of any status except sleep and paralysis
You really don't see the problem with Exploud taking a Toxic as it switches in to say, SpD Alomomola, and then gets promptly Protect stalled? Pretty much every Pokemon hates taking status with a few exceptions. This is worse for Exploud because unlike Camerupt, it can't take advantage of a free turn granted by Protect stalling to do anything.