Right... Tony Kushner (on Amanpour) said it was no concern of his who Andrew Garfield went to bed with at night, only that he could play the part of Prior Walter.
and I can't recall too many times Paul Newman played a Jewish character. He always seemed to play Irish or WASPs--and quite convincingly.
Ultimately, it's what's onstage or screen that matters to me, not the off stage stuff.