Technically, supreme would imply the highest, but even if he believed that, why is it a problem (aside from being inaccurate)?

Certain groups of black men are taller and stronger, on average, than any other sub-population of humans. When I watch the NBA, which selects for the far-far-right tail of the distribution in height and strength, it's not surprising that an astonishingly large majority of players are drawn from those groups. I'm not surprised to see zero women. I'm not surprised to see very few white men, and even fewer Asian men able to compete at that level.

Does that make me a black supremacist or something?