Secondly, I'm using the words "powergamer" and "roleplayer" as ways to describe two ways of playing - one where the player knows the game well and knows that they should put all their points into characteristics, and a second that does not know the game as well, and is not planning ahead as well (and doesn't know that they should put their points into characteristics).
I think this "definition" is the core of the issue, and it's misleading. What you're saying is "power gamers" know the game, and "role-players" are just ignorant (in the best sense of the word). But it seems like a really small deal. Unless you're making a "character for life" it's easy to do it right the next time. And if you are making a character for a very long running campaign, then the GM should be flexible enough to either let you re-stat the character once you understand the concepts, or allow you to create a new character with the same XP as the old.
It's like any other game. Are you going to change the rules for Monopoly or Risk because there's a new player who doesn't know what's going on?