Since Dynamax is gone, I want to discuss some of the winners and losers of the ban. Please correct me if something here is wrong :x
Winners:
Fat Stuff:
(probably more that I missed)
With the loss of Dynamax, and thus the loss of a sudden increase in offensive potential, fat Pokemon such as these are able to survive for much longer and function more effectively as defensive checks. Defensive cores will be quite a bit harder to break, making fatter teams a much more appealing option. It's also much easier for these Pokemon to come in and abuse choice-locked Pokemon now as well. Although there's still no shortage of offensive Pokemon that can do a number to many of these Pokemon, at the very least a massive weight has been lifted off the shoulders of these picks. I'm especially excited to play with some of the new HDB options such as Avalugg and Flareon, which will be much easier to pull off with Dynamax out.
Aegislash:
Aegislash is in a great position with Dynamax out of the way, and is definitely a threat to watch out for. Pre-Dynamax ban, it wasn't able to abuse it quite as well as other Pokemon due to its low speed and the fact that it can't abuse King's Shield to switch forms while in Dynamax, making it quite squishy and vulnerable. Not to mention that it struggled when facing other Dynamax abusers thanks to a lack of reliable recovery, meaning its only option bar switching was King's Shield spam. Now with Dynamax out of the way, it doesn't have to worry about threats suddenly being able to live a hit from it or being able to muscle past it. Once again, it can also abuse choice-locked Pokemon as well, giving it a free attack. Although I've personally seen mostly Sub or SD sets, I think Choice sets should be given a lot of spotlight too just because of how well Aegislash can abuse free turns.
Dugtrio:
Duggy is back! Now that Pokemon can't suddenly became much bulkier out of nowhere, Dugtrio is able to abuse good predictions or free switches in order to trap many of the big threats in this meta such as the omnipresent Tyranidrill combo, Bisharp, Dracozolt, Cinderace (if Jolly) and some up-and-comers like Flareon. It's also able to effortlessly trap weakened threats now that they can't dynamax to live a hit. I'm also in the camp that thinks a Duggy suspect is likely coming, since Dynamax was one of the main things that stopped it from being really strong. At the very least, Shed Shell is likely to be me the new big item on Toxapex again :p
Darmanitan-Galar and Dracovish:
Although both of these Pokemon will miss being able to max to break the choice lock and gain extra bulk, the fact that things can no longer counter max against these threats - gaining additional bulk - mean that they'll have a much more consistent time cleaving through teams. Darm-Galar in particular really appreciates this, as it was prone to getting maxed on by mons such as Togekiss, which could live one Icicle Crash while maxed if Darm wasn't banded, and KOing back with Max Airstream or a supereffective max move.
Losers:
Ditto:
Now that offensive threats are much easier to deal with, we simply don't need Ditto as the primary revenge killer anymore. Although Ditto will still have a place in the metagame no doubt, we no longer have to rely on Ditto Dynamax countersweeps (thank goodness).
Choice Abusers:
(these come to mind, but there's almost certainly more)
Now that choice abusers can't break the lock with Dynamax, it's much easier to punish them when they make a wrong prediction. It's also much easier to revenge kill them as well, since they're no longer able to get a sudden increase in bulk at any point. Some sets such as the Choice Scarf Nasty Plot Rotom-H no longer function since you can't Nasty Plot and then Dynamax to break to the choice lock. Over all, choice users will need some solid prediction in order to really pull their weight now.
Max Airstream Spam:
(these three were the main ones)
(shoutouts to these guys though)
Now that Max Airstream is dead, it's much harder for some Pokemon to acquire boosts and sweep. Gyarados now must rely solely on Dragon Dance in order to boost speed, making it much more easily pressured and revenge-killed. Togekiss is unable to boost its speed now that max Air Stream is dead, meaning Nasty Plot sets are much more likely to die off completely since Togekiss currently can't Roost like it could in previous gens, meaning Scarf sets (or maybe even Specs) are likely to become the norm. Either way, I can't see Togekiss staying in OU now that it can't abuse Dynamax to get some quick sweeps, as I don't think it's nearly as good as many of the other defensive options we have. Although Bulk Up Corviknight will still be a good late-game wincon that abuses passive threats, Max Airstream being gone means it can't boost its speed to better deal with offensive threats. Also RIP Braviary, Charizard, and Rotom-S, who I felt were OU viable only because they could Dynamax to get speed boosts and then sweep/break. You all will be missed.
Also let's not forget that Dynamaxing gave increased bulk to all of these mons, making them both offensive behemoths as well as incredible difficult to revenge-kill.
Rain:
Can no longer max to set up their weather again, meaning Pelipper is going to have to be played more safely in order for these teams to really shine. No more maxing also means that rain sweepers are much easier to revenge-kill, and it will also take more effort to get sweeps going then simply clicking the max. I think Rain will still be potent, but definitely much more bearable.
Mons that were only viable through their GMax:
(these are the only two that immediately spring to mind)
Any mon that relied on their GMax's Max Move in order to be competitively viable is now dead.
Other DMax sweepers:
(there's definitely more, these are just the main ones)
All of these Pokemon were also great DMax abusers that will definitely have a harder time sweeping now that DMax is gone, as they can no longer abuse DMax to get the increased survivability, secondary effects, and extra power that all of these Pokemon really benefited from. Excadrill in particular gets knocked down a peg since it can no longer set up its own Sand, making it nowhere near as self-sufficient. Hawlucha is also no longer able to set up its own terrain, meaning that it has to rely on teammates or more gimmicky items to activate Unburden; not to mention that it can't abuse Max Airstream anymore either. The loss of extra bulk really hurts mons such as Gengar, Hydreigon, and the Rotoms who all had no way to boost their speed, and without Dynamax they're no longer able to take extra hits thanks to the additional bulk; meaning that they're much easier to revenge-kill. The other listed mons also really hate the loss of the extra bulk that dynamax provides.
Please let me know if I missed anything!
EDIT: Made a couple of corrections.
