The term metalhead has been around as long as metal. I don't see a reason to stop using it and I don't think it represents us as "dumb". If people want to think that about us, fuck 'em.
When people I don't know say i'm a metalhead i'm just like yeah whatever, but when someone who knows me swings that word around I want to slap them in the fucking face.
Are you the kind of person that corrects people by telling them "I don't play video games, I play COMPUTER games!!!" as well?
I don't mean every fucking single metalhead who ever existed, just the ones who label themselves as "metalheads" and know nothing about the genres metal came from. Like the ones who act like thrash is "slightly hardcore-influenced" metal, if you ask me thrash has even more elements of hardcore than it does metal!
A more correct name for this thread would be "a rather large percentage of metalheads are fucking retarded"