I think it's the fact he seemed more interested in bringing attention to particular games like GTA:SA rather than bringing total focus to the game ratings, the lack of control over kids easily getting their hands on these games, etc.
I know he's using GTA as an example, but when his message comes across that GTA=bad, rather than apparently his intended message of ratings not being strict enough, then he'll lose some people already who are tired of hearing about goody goodies trying to look out for whats best for us.