On Poison Heal
Why Poison Heal Set-up Taunt are broken?
Heavily agree with this. We all agree that there is something broken about Poison Heal rn, and while council (and several others in discord) are leaning towards VQD being more troublesome, I strongly disagree with it, as banning VQD is not only a worse option than banning PH, but it also doesn't solve the problem.
Tera is a completely different issue, it enhances the already busted Poison Heal but Poison Heal without it is still broken. I have a long Tera discussion post planned but its too long so I'll post it separately probably after tour ends.
Why is Poison Heal broken and suspect worthy?
Tea does an excellent job of going into detail on this subject in this
post, but basically, PH is incredibly splashable, super hard to punish, and very difficult to defensively check. What Tea didn't get into is the number of viable Poison Heal users. Almost every single Pokemon that is not a Steel- or Poison-type can viably run Poison Heal, and when one considers how many distinctly different Pokemon that is, it is easy to realize how its very very difficult, arguably near impossible, to prepare for all of these.
The many different Poison Heal abusers:
While the most common Poison Heal users we see are stuff like Groudon, Fairyceus, etc. There are so many different viable options, and each with their unique typings and stats demands different checks. Even users that would be weak to meta threats/revenge killers like Zacian-C and Miraidon are completely viable, not even considering Tera. For specific examples of viable users we have:
Giratina-O, Mewtwo, Palkia-O, Rayquaza, Koraidon, Miraidon, Groudon, Kyogre, Palafin-H, Ursaluna, Arceus-[Not Steel or Poison], and more.
Not only do the types not share checks, but even for the same type the Poison Heal Pokemon can be physical or special. e.g. You switch-in an Ice Scales into PH Fairyceus only for it to reveal VD Torque.
Thus the only "universal" PH check is Toxic Orb Imposter (and Misty Terrain to delay orb proccing entirely). And even for Imposter, several Poison Heal sets have the ability to bypass it, especially with Tera.
What this means for the meta is that its an incredibly matchup based meta. If you brought a Poison Heal user that your opponent did not prepare for, then you straight up have an enormous advantage. Note that this is different from previous metas because Poison Heal as a whole is very difficult to soft check, and all of these sets are viable. Previously, say you brought a MMY that has a good matchup, your opponent can still play around that MMY by trying to inflict status, play with predicts, using Imposter effectively, etc.
On why VQD is only problematic on Poison Heal:
We have established that Poison Heal as a whole is an issue (and that banning individual mons does literally nothing). Now, Tea mentioned in his post that banning PH could lead to other setup sets like bulky FurScales setup that also abuse VQD, and thus PH ban would not completely solve the core problem.
However, as DF-Shock mentioned in his post already, these alternate setup sets have big disadvantages compared to Poison Heal: They are vulnerable to status, they need recovery since they do not have the passive, infinite recovery that PH offers.
Being vulnerable to status is a big deal. Burn completely cripples physical sets, Paralysis is annoying for all sets, and (assuming a PH ban), poison sets a timer on all these sets. As a minor note, lack of immunity to status also means some status utility moves like Wisp and Glare are less desirable because of potential Magic Bounce.
Needing to run a moveslot for recovery is also significant. Currently PH users only need a setup move and a STAB move, with two free slots for coverage and utility. For non-PH setup, they need to add a recovery move, meaning they either have to forgo coverage or utility. Forgoing coverage means it struggles a lot more against resists, while forgoing utility like status inflicting moves or Taunt means defensive mons have a lot easier time checking it through status moves, recovery, or counter setup.
Also, by running recovery, these sets are also more vulnerable to Imposter. Physical setup sets would be forced to either have trapping or run leech seed (or some other non-orthodox option) to deal with Imposter, while special sets need ways to significantly damage Imposter without getting PP stalled (Judgment).
So overall, non-PH bulky setup, while can definitely be good (we already see this in Ghostceus and QD Miraidon), is overall less threatening, less splashable, and easier to answer.
On why Poison Heal is still busted without VQD
One reason why people propose to ban VQD instead of PH is that PH will be hurt significantly without it, but I disagree with this. Outside of VQD, we still have CM, BU, Tidy Up, DD, SG, etc. Since the latter 3 don't boost defenses and will have more limited users, we'll just consider CM and BU as direct replacements.
The main difference here is obviously the speed boost, but how significant is this speed boost in the first place? Poison Heal Pokemon, due to the lack of a boosting item and ability, as well as general reliance on slightly weaker moves for PP, are significantly weaker than wallbreaking sets. Not even boosted moves will generally OHKO foes, especially notable in a full EV meta. Thus, if the opponent brings in a Pokemon that can OHKO said PH user, then the speed boost really doesn't matter that much, you still would not stay in unless you have a specific status move to survive or you decide you want to fish for a Scald burn or something.
If the opponent cannot OHKO you (so 2HKO), then the speed boost matters here if you can 2HKO them, but even without the speed boost this is still a winning matchup. You simply trade hits, and then switch out, because through Poison Heal you can heal off the damage taken easily, while the opponent likely cannot (revenge-killers are typically choiced or sets without good longevity). Slow pivot into revenge-killer is also punished by Substitute, a completely valid move on multiple Poison Heal users.
Also, if we consider the specific PH users, we notice that they are all quite fast. Most have minimum 120 speed, so being outsped is limited to a small pool of Pokemon.
Finally, the speed boost does not even matter for defensive counterplay. Unless a VQD ban suddenly leads to a surge of popularity for fast defensive mons like Eternatus, the bulky boosts from CM and BU still means that the defensive counterplay against PH is the same as before (nonexistent). So its still going to be matchup fish just like rn, except theres an extra layer on if there is an offensive revenge-killer to provide a soft check for a few turns.
TLDR
Poison Heal is busted and makes game not fun, VQD is not busted on non PH sets, PH without VQD is still busted, suspect PH
Other stuff
Already talked about Tera; Moody is pretty uncompetitive and just luck cheese, bringing nothing competitive to the game, might as well get rid of it; Gorilla Tactics is strong for sure but I haven't seen that many good abusers; Zacian-C is incredible and definitely worth suspecting after PH and Tera, Band sets are not the only sets, go check out quojova's latest series in the no johns tour, that set is just one of many Zacian-C can viably run.