Just because you disagree with their political views doesn't mean you can invalidate everything they've experienced as a minority. Yes, black people can have right wing views too.

Labelling them as Uncle Toms or clearly white people in disguise is racist. Not only to suggest that they're some sort of traitor to their race because of their views (based on their own experiences no less) but to even say that they couldn't possibly be black for thinking like that.

I'm a dyed in the wool socialist but people of every background and political leaning should be encouraged to share their views. People on Reddit can't handle a black person speaking their mind if it doesn't align with their own views, and worryingly a lot of the left-leaning subs are no exception.