Well, to be fair (and actually, I'm not being fair), Alyssa Milano and Rose McGowan are always speaking out against crap Trump does, and both of their careers were so washed up at one point in their lives that they were basically reduced to doing porn.
But you have to remember, Muhammad Ali was from a time where reprecussions for being "anti-American" were much, much more strict, especially during the conservative McCarthy era, where there was actually a Hollywood Blacklist, where show-business people who were suspected to have ties with Communism were forbidden to employed in Hollywood: Mr. Hooper himself was on that list.