For trials speedrunning, it can help for wall jump cancel (by binding dash and jump to the same button) or specific strat's in some levels (jump + shoot in TowerForge III).
So I discussed that with members of the TowerFall discord and some Celeste speedrunners, and they seem to agreed that it should/could be allowed as long as the players are not using macros and it's fairly accessible. For the last point, I think that it's good because some steam feature let you rebind controls like that even with non steam game, and even without a third party app, I believe you can do the same (even though I never got it to work).
this is different for celeste because the game comes with that functionality by default. what about switch, xbox, playstation? what about non-steam installations?
As I said, for PC as long as you have Steam, you can rebind your controls with non steam game. Indeed I don't know how you could rebind on consoles, but I doubt anyone would try getting Trials WR on console (and I doubt at this point it is even possible)
IF there's not some game breaking thing that can happen I don't see why not. Honestly even if there was it's still good accessibility, so I don't really see why not
