>>52260537>>52260673It's not a precedent or a "can of worms." It's a broken signature move that only one Pokemon currently learns. Banning Last Respects only affects Greavard (and possibly Basculegion in the future), and Greavard would not be broken without it.
This is different than say, banning Libero from Gen 8 OU (which would unfairly affect Raboot and Scorbunny), banning Protean from Gen 6 OU (which would unfairly affect Kecleon), or the oft-cited hypothetical of banning Speed Boost on Blaziken only in Gen 5-7 OU (a complex ban). This is a simple ban: banish Last Respects, which currently has one user, to Ubers instead of Greavard.