For Houndstone, the problem is the combination of an ability, a move, and a Pokemon with enough viability to make that combination effective. Banning a pokémon is the best option and continues to be given how most, if not all, complex bans ended up being patchwork that didn’t fully address the issues they intended to fix. Houndstone was able to abuse a speed tier, use a move with no defensive options, and do so with little difficulty because there is multiple sand setters and little defensive counterplay to a 150-300bp move.
We did the same thing with Dracovish in Gen 8, yes other mons get Fishious Rend but none of them get the combination of a stellar typing, an ability to make that move even stronger, and a speed tier that actually gets Dracovish the opportunity to use Fishious Rend. That isn’t to mention the ease of setting rain for it either.
Last Respects is the issue, but then we tread close to the “well x,y,z is balanced if you take away x,y,z from the mons move list, abilities, etc.“ That is worst possible way to balance something, because new players will come to comp pokémon and have no idea why so many pokémon have these seemingly arbitrary restrictions.