That white people reject all things related to black people, except the parts that white people like. That's a great deal of the "systemic racism" that seems so hard for some white people to wrap their heads around.
Music shouldn't matter. Cultural icons shouldn't matter. You don't have to like these things or even like the people who like those things, but there's a perception that the people who say things like that post are putting all the black people who like that stuff into the same... category.
And, there's an element of hypocrisy if certain segments of white culture will, on the one hand, say black people should not hold up convicts and foul mouthed performers, while some of those same segments idolize slave owners and foul mouthed reality-TV-star-politicians.
Perhaps, but there is a very real perception that many white people think in terms of "good" and "bad" black people, with lists like that reinforcing that perception.