If we all agree that a people can experience trauma on a large scale and that trauma can then pass onto the descendants, then the reverse must also be true – a people who have inflicted trauma on a large scale pass that experience onto the descendants.
People who are descended from people from slave-owning and imperialist nations carry with them the scars of slave ownership, genocide, oppression. It shows in the way they act, speak, think. Their worldview is informed by their history as masters of “lesser people”.
Also being the first generation to break out of that opressor mindset is tough. Like your family, lots of friends, etc are all evil. And you have to rebuild your social life from scratch or just put up with being surrounded by evil assholes.