The idea is that, in the future, apps can do anything *if* they have permission to do that thing. You'll trust the app that edits permissions to edit permissions, but you won't give that permission to video games and whatnot. This greatly limits the risk.
Android has already implemented this system, so it definitely can be done. It won't protect irresponsible users from the consequences of their decisions, of course, but the only winning move in that game is not to play.