Rourke didn't get respect for years because he was anti-Hollywood before it became fashionable.
Sean Penn and Johnny Depp, both list Rourke as a huge influence, and kind of went the anti-Hollywood route a bit, themselves.
They, on the other hand, are both considered geniuses.
They are, I'm not arguing that, it's just that you're right, Mickey Rourke will never get his due.