Read the book Noughts and Crosses https://www.malorieblackman.co.uk/noughts-and-crosses-2/

And watch the TV programme of the same name then read the posts about it and you will begin to understand how white people think and feel about the subject.

An all white cast of Roots, well that would be a thing. And the uproar would be something to behold, because it would be white doing it to white.