Why a Belly Drum ban is not happening
This will be my final attempt at articulating why we are so adamant that a Belly Drum ban is not on the table, and in larger part, why tiering policy is the way it is.
As I am sure you are well aware, Smogon prioritizes banning Pokemon over moves / abilities / anything else; only if a move / ability / etc is broken on a wide range of Pokemon, usually accepted to be all or a vast majority of fully evolved users, is a ban on the move / ability considered.
OMs add an additional layer of tiering for their specific mechanics; since this is mostly about AAA and Belly Drum, I'll just be referring to abilities here. We still prioritize Pokemon bans first; if an ability is only broken on one Pokemon (Sturdy Shedinja being the most famous example), we ban the Pokemon. If the ability is broken on a wide range of Pokemon (usually 3-5, but this is a bit more subjective) then we look to ban the ability instead. This layer of tiering
only applies to the mechanics related to the OM; AAA can't restrict moves, STABmons can't ban abilities, etc.
The reason for this is simple; very few abilities are universally broken, but it's the combination of the stats, typing, and movepool that cause a Pokemon to be broken. Even abilities as bonkers as Wonder Guard and Huge Power are not broken when restricted to Pokemon with one HP or 50 Attack. Similarly, Sheer Force is not broken on every single Pokemon in standard play, but only ones with a high enough combination of stats and movepool to break it. So in most cases, we ban Pokemon since they are the combination of all the things.
In OMs, we follow the same principle. In AAA, we ban mons first, abilities second, and only in cases of a move being broken on every single fully evolved user do we seriously consider banning a move. Recent examples include Last Respects, Shed Tail, and Revival Blessing, as they caused shenanigans on all their fully evolved users and across multiple abilities.
Looking at Belly Drum specifically, there are two Pokemon currently banned (Hariyama and Iron Hands) due in large part to Belly Drum. A third, Ursaluna, is currently being suspected. Especially if Ursaluna gets banned, and
especially if a new Pokemon rises to take its place, this is a pattern. But, what is the pattern really?
Belly Drum is
not the only thing tying these Pokemon together. All of their sets rely on their high Attack, Drain Punch, and Triage as well. Without any one of these elements, the set falls apart and is not broken. It is the combination of all four things that break these Pokemon.
Similarly, we can fairly definitively say that not every Belly Drummer is broken in AAA. The full list of fully evolved Belly Drummers is:
Even if Ursaluna gets banned, that is 3/14. Charitably, maybe Chesnaught can Charizard could also be broken, but I am skeptical, and even then we are looking at 5/14. Not even half of the fully evolved users are remotely broken with Belly Drum, and looking at the Ursaluna thread, it may well only be 2/14.
I alluded to the fact that all three of the considered Pokemon also rely on Drain Punch; why would Belly Drum be a "better" ban over Drain Punch when it's on exactly as many broken sets? Shadow Ball by my count is key to six different Pokemon being broken (Flutter Mane, Gengar, Zoroark-H, Spectier, Dragapult, Gholdengo), double as many as Belly Drum or Drain Punch; should we consider a Shadow Ball ban to free all of those? No, and it would be ridiculous to.
So, how do we determine what we take tiering action against? Currently, we are in the "mons" stage, since only two users are broken. If we get another one or two, since all of them rely on the same ability, Triage would be the next correct ban by our tiering policy; this removes the ambiguity of "what part of the set do we remove to balance it" since the answer is the part that our OM adds in. I do no think there is any reasonable argument that after a Triage ban Belly Drum continues to be an issue.
This ended up being way longer than I expected and rambled a bit, but ultimately, tiering policy here is clear. We currently have 1.5 mons banned "due" to Belly Drum, and at most are looking at 4-5. Belly Drum is an arbitrary ban, it's not even the only unique move on the sets. There is another ban that is more correct in our tiering policy, and our tiering policy helps keep things consistent and avoid the messiness of "what is actually the correct ban?"
We have confirmed with the tiering admins that this is the correct play; we are not going to ban a move that isn't broken on the majority of Pokemon that learn it cause 1.5-5 Pokemon are broken with it. Especially not when a Triage ban also solves this issue, if it even extends beyond Hands / Haryiama.
I can't make you stop talking about Belly Drum, but hopefully this makes sense and gets it across that the decision is final and goes even above the mod team here. A Belly Drum ban is not happening, and arguments made to me, Isaiah, or any other mods here cannot change it. If you think Ursaluna, or Triage, or somehting else should be banned, would love to hear it. But hopefully that makes sense.
This mon has a good match-up against most of your team. You kind of just have to pray that it is not Specs or else you will have to play out of your mind and get every predictions right. If it is Scarf then you are ok-ish since you can always switch to Muk. If it is not choice then try to dance around and heal up Muk. 
The best way to win against strong wall breakers are to play aggressive and clean up with Talonflame. Try to keep Muk at high health and don't let them get in.
Lucario and Enam-T put a lot of pressure on Ursaluna, but if Ursa gets a BDrum up it might be lights out. Solid play is enough, most of the time, especially since Ursaluna sets lacking Heavy Slam / Gunk Shot can't hit Enam-H for good damage. Still, though, Ursaluna (and to a lesser extent, TriageDrum Chesnaught) put a lot of pressure on you from the start of a match.
