I think some are confusing CHARACTERS they don't like with bad acting performances, specifically in the cases of Diana Muldaur, Ethan Phillips, and Chris Pine.
Phillips was GREAT at portraying a very annoying character, just as Muldaur played a crusty McCoy-esque doctor well, and Pine played a juvenile punk Kirk very well.
At least I think so.
Pine IS a juvenile punk, so it's not that much of a reach. He's just playing himself.