If a certain character or Pokemon is shafted in the show, that makes many people root for them essentially. The fans often, however, get very frustrated that their screentime is stolen from those who either have enough of it or are the writer's favorites it seems.
At the end of the day, which is more irritating as a fan to you, a Pokemon or character who is overexposed, or a Pokemon or character who gets shafted.
For me, it's definitely the shaft. On this show, there's always going to be favorites, fanboys, fangirls, etc. But there are those who don't have ANY, who IMO truly deserve some, and who are there because the writers want what they perceive to be as a BALANCE.