The thing is, in that era the “bad boy” thing was a positive thing. In the OP’s examples, the bad boy vibe they gave off was a big part of their sex appeal. This would NOT have been acceptable, in any way, in a non-caucasian actor. If Poitier hadn’t been relegated to roles of The American Negro as Noble Victim, as a way to make white Americans feel just guilty enough to borrow some of his “nobility” but not *actually *guilty enough to consider changing the status quo, he never would have been allowed such prominence. If he’d started to give off sexy bad-boy vibes to the white wimmins in the audience, his career would have been over before it started. None of the non-caucasian bad guys of the era were sexy; none of the sexy non-caucasians of the era were anything but nobly asexual.
You’ve summed up my gut feeling very well on the issue in regards to Hollywood. Though ‘dangerous’ musician types (Miles Davis, Chuck Berry) seem to be the exception