But you've given no serious evidence that he has a dodgy attitude. He's a member of a minority himself, married to a member of a minority. The kinds of films he was in, though they aren't my cup of tea, are ones that are watched and enjoyed my members of minority groups as much as by MC white people - in fact I suspect that MC white people aren't their most prominent demographic.
What you seem to be saying is very reminicint of "if you don't vote for me, you ain't black" which is to say, a view that says that people of certain races need to toe the political line or they don't count really count as members of that group - they are just Uncle Toms presumably. The common less obviously hypocritical approach ignores it when members of minorities take a certain viewpoint but accuses a white person who says exactly the same thing of being a racist.
A good rule of thumb is, if someone black or Asian said something, and you wouldn't call it out as racist, don't do it when a white person, or someone you think is "white adjacent," says it either. Make the argument that whatever it is is a problem, if you are right you should be able to do so effectively. If you have to resort to that kind of id politics level of reducing people to their racial group status there might be a problem with what you are trying to say.