White and black men do not retain upper income status across generations at equal rates. White men who are born to wealthy parents are highly likely to remain in the same wealth quintile (something like 60-80% do), while black men who are in the top quintile are about 20% likely to end up in a given quintile, including the one they were born into.

Affirmative action is important even to wealthy black families, if the goal is to mirror the mechanical flow of wealth in America's white families.