A group of officers all one skin color picking on someone because of skin color are the acts of supremacists. He was singled out because of his skin color.
If you're alleging they targeted Tyre Nichols based on his skin color, that's an anti-Black action. I'm entirely comfortable with the idea that minority groups can internalize bias against their own identities, but that doesn't seem to be your argument.
"Black supremacists" believe the Black race is inherently superior to other races. This means it would be very, very odd for them to beat someone up for being Black.
Edit: I wasn't incorrect, I can't see your post anymore but I don't remember you specifying metro in it. Additionally, I can process the not-new idea just fine, I just think you're applying it entirely incorrectly. I'm done here.