I think it comes down to education and tribalism. Take your average American of any race and their history education (which is abysmal), then take your average black American, their general subpar education and lower IQ. What information they do get from "African-American studies" is highly biased towards victimhood and CRT. Tribalism takes care of the rest - it's just nature to gravitate towards those who are most like yourself.

I grew up in a predominantly black school system. It was awful, but that's besides the point. The black kids actively hated and were encouraged to hate white people. Slavery isn't really their concern, which is why we hear crickets about actual real slavery still happening today. Black well-being isn't even their concern, or else we would see a lot more talking and action about the regular mass slaughter happening in Chicago, for example. It's about vengeance and hurting whites because they feel it's their right to do so. And so, it's generally inconvenient to focus on the Africans that started the slave trade to begin with.