Point = obsolete, imo. Every kid browses pr0n sites nowadays, what's stopping it from entering this site or installing the game? These ratings are BS, no doubt bout that.
You're welcome to propose people abolish ratings for games and movies entirely if you like, though I doubt that will go down too well with the general public.
Ratings serve a very important purpose, and the fact that it's possible for children to see content that's not appropriate for them doesn't change that. Ratings provide a guideline by which parents can judge what sort of content they can expect to see in a game or movie, and whether it's appropriate for their children. After all, parents probably aren't going to want to play every game they buy for their children themselves first to see if they're appropriate for their children, especially if they're not gamers themselves to begin with. Sure, an M rating won't stop parents from buying a game for their children, but if the parents were doing their job, that wouldn't be a problem, because if parents don't want their children to see 3D animated dismemberment, than they shouldn't be buying M rated games for their children. And if parents are worried about their children looking at pormography, than maybe they should supervise their internet usage and not let them visit such websites in the first place.
I don't want an A rating for Skyrim, while I am sure I would like the uncensord creativity of the game, it would greatly impact Beths sales. Which would be bad, these games cost 10s of millons of dollars, so Beth need to make alot of beans so they can keep making them to there high standards.
Getting an M rating really doesn't stop a game from having good sales. In fact, some very successful games are rated M, tak GTA, for example.