Have you considered that usually our economic status is inherited from our parents? I mean, my parents were middle class, so my brother and I are middle class too. We are lucky and also the norm. There are plenty of studies that said that social mobility is very limited and that very few people can improve their economic position.

Now, some families made their fortunes with slavery. While is true that now slavery is illegal, the money they won selling people, was inherited by their sons and passed over to grand son, and so on.

On the other hand, black people who gained their freedom, did without money. They usually were poor, so their children started to work young and had less opportunities. That also meant that they didn't passed money to them, so the situation continued several generations.

The point is, if your father gives you a loan of 1 million dollar to start your first business, you lose that money and your parent gives you more money, it is easier to get rich even if you are bad at business ( and that is being generous, many people would consider someone like that the epitome of incompetence). On the other hand, many people would never see 1 million dollars in the first place.

Slavers and plantation owners made a lot of money out of slavery to invest latter in other things. We want to pretend that their offspring being rich too is because they have "talent", but no, they just have money and contacts among other rich people.

So if I were descendant of an slave, I would foster resentment against the slavers descendants who inherit riches earned from selling my family. Seems pretty straight forwards to me.

Sure, some white people doesn't descent from slavers, but we still have the advantage of not having extra obstacles in our life. As simple as that. If you can't see it, then is probably because you have been cooed all your life.