bisharp is OU because of many more things than just knock off:
dark type is a very good defensive type as it is now the only type that resists both dark and ghost attacks, especially ghost
dark type is now a very good offensive type since steel lost the resistance as steel is a very common pokemon type
defog being buffed to the extreme is actually a big buff to defiant pokemon, bisharp is the most notable for having STAB on a really strong priority attack and having a crazy strong attack stat behind it, giving it swords dance lays the smackdown
he’s the only steel type to resist both dark and ghost attacks
he’s a dark type with a secondary STAB that hits fairy type pokemon
knock off becoming one of the top 5 moves in the game does help as well
knock off is literally given to every pokemon (not really, but god damnit does it feel like it), chansey could come in on thundurus-I only to find out that he has knock off, mega venusaur? knock off. hell, alakazam can learn it, it’s distribution is so fucking amazing that you just can’t tell who gets it and who doesn’t and because of what it does, it’s viable on like…everything
crawdaunt’s problem is that his role is done by azumarill but much, much better. while crawdaunt deals more damage, azumarill has an infinitely better defensive typing to go with some great natural bulk. both are slow and are water types with a fuckton of power. azumarill’s bulk allows him to switch in a lot more often. it’s the only reason why crawdaunt is not OU. Also being weak to mach punch really hurts him, he might see more usage when mega lucario inevitably gets the boomstick up the ass and shot out of a cannon into ubers
infernape should’ve been UU last gen, and somehow it’s UU this gen when it’s a much better poke this gen (108 not being the golden speed, no more perma rain, fire stab is the single best stab to have currently, good priority, great coverage, threatens most mega pokemon with his awesome coverage, great utility in Rocks and u-turn, etc). it really only lacks power and that’s because its power isn’t fucking stupid like what you see in most of OU
also, smogon’s base tiers (OU, UU, RU, NU, maybe a new one gets made this gen due to the amount of pokemon) are entirely based off of usage. the cutoff point is roughly 3.41% or 1 out of every 25 teams. Ubers, BL, BL2, BL3, etc are ban lists and smogon has a say in what goes there
just be happy crawdaunt can be used in UU, staraptor will forever be BL