But we’re comparing whites and blacks in America, so the old “but people are starving in Africa” doesn’t apply here.
So why is there a disparity of family wealth between whites and blacks in America? Any alternative theories? Because “but the bombing of Dresden…!!!” does not explain it.
As for your question, I do not have any theory. A viable theory would have to explain the variation of the black-white gap across the US.
Looking for data, I found a graph mapping the differences of average black and white income (not wealth) across U.S. states:
https://www.stlouisfed.org/-/media/project/frbstl/stlouisfed...
If racism was the only root explanation, Pennsylvania would be more racist than Georgia and Wisconsin more racist than South Carolina. That does not seem plausible to me.
People have even less family wealth in less stable places, plagued by war, genocide, forced expropriation, violent regime changes, state bankruptcies etc. For example, both Germany and Poland were big heaps of rubble in 1945. Nothing to inherit there but destroyed, burnt-out cities.
The 20th century in general was pretty awful outside North America. If bad history was such a universal determinant of future failure or success, the world would be one giant hopeless poverty-stricken hellhole.