Are you even aware that most language do make a difference between byte streams and character streams? I've never seen a language where you had to decode byte streams from a file. You seem to be living in some insane fantasy land where people actually have to do this. If that was actually the case, you'd be right, it would be stupid.
Thing is, that is not the case.
If you're not going to argue about the real world, why should we bother listening to you?