+3
I think calling it an "alternative" to censorship is a misnomer. It doesn't censor, it classifies. That businesses make decisions based on that classification matters, but it can never really rise to the level of genuine censorship, thankfully.
I think having a rough idea of what's in each film is a useful tool, but a) it seems pretty clear that its rating methods are fairly capricious as-is, and b) there are lots of private entities that do a pretty good job breaking it down. You could make a very good case that it isn't that necessary, and an even better one that it should probably be a bit more consistent about its rating methods.
The only word of sympathy I'll offer is that, as the owner of a forum with actual rules on it, I can appreciate how difficult it is to draw lines about what is and isn't acceptable. There is no way to do so in a way that can't be made to look foolish in some cases. I assume the MPAA dislikes making specific, public "rules" for content for exactly this sort of reason; it sounds silly to say, for example, that two f-bombs are acceptable, but three aren't. But that's an unfortunate byproduct of any attempt to grade content.
I think, over time, people are going to care about ratings less and less, though. There's a good chance neither reform nor formal abolition will really be necessary, because it'll simply cease to be relevant.