The issue is this is impossible to quantify properly, everyone must have benefited from slavery somehow because it was so widespread in the past. It’s quite likely that someone’s ancestors were slaves or owned slaves at some point in history, maybe even both. It doesn’t matter your race or were your family is from, the term is heavily associated with black people due to modern American slavery but the world itself come from white slavic slaves who were often forced into slavery during the middle ages. Also, it was a very lucrative business so a lot of people where somehow involved with it.

Another think equality complicated is genocide, everyone’s ancestors where somehow involved with it.