Yeah I agree. The dressing room cannot be a happy place knowing that some players get away with consistently poor performances and never seem to get dropped, while others know that a single mistake they make will provoke the manager to single you out in a post match interview.
Maybe it's just me but I always dislike managers who pick on individual players and blame them for defeats publicly.
If a player makes an obvious mistake that leads to a goal I think it's fine to say "yeah he made a mistake".. but to constantly blame them for defeats is really unacceptable.