The Belyayev fox domestication experiment shows that it does not take many generations (6ish) to turn a wild fox into a cuddly domesticated fox that whines for humans.
The selection pressure humans are under is not that strong, but still my intuitions expect that 400-800 years is enough to see moderate psychological changes.
Ashkenazi Jews are confirmation of this: 800yrs isolation+selection for success in financial jobs, resulting in increased intelligence, particularly verbal intelligence (with the side effect of several genetic diseases). Any ethnic group under relative genetic isolation for 400-800 years will have small genetic cognitive changes matching the selective pressures in their culture.
Mass religious killings, forced conversions to Abrahamic religions, and discrimination against heretics/etc (aka anyone who stands up for an idea that differs with the orthodoxy) have gone insufficiently avenged for 1000+ yrs in European history, I expect similar things going back to the start of civilization. Other cultures have different but related problems.
Conclusion: most modern humans are the genetic product of thousands of years of selection pressure towards domestication; and people of European and Middle Eastern descent are the product of 1000-1500 years of selection pressure by a culture that uses societally endorsed exploiters to use lethal force to demand submission to authority.
Being a societally endorsed exploiter within that system was genetically successful, as was keeping one’s head down and disassembling all but minimal agency so as to not appear a threat, or having all intact agency be visibly serving the system and/or the societally endorsed abusers. Most of the nongood undead types are visibly shaped by this.
People with a fundamentally altruistic utility function have not much reason to play along with this, which counterfactually could have led to it being genetically eliminated. However, each human has two halves of the brain each with their own utility function, and the vast majority of people that have fundamental altruism have a headmate that has a fundamentally self-interested (aka nongood) utility function, and these nongood cores are generally able to steer the combined human from being too rebellious. (Also, I don’t yet know the degree to which the altruistic utility function is hereditary, as opposed to a difficult-to-get-rid-of glitch inherent in deep machinery.) My intuition is that the genetic advantages of being locally socially altruistic have been approximately balanced against the cost of early death from injustice. People with the altruism glitch have historically almost always been constrained to small domains like helping their neighbors or interest in eg: sustainability, both by misplaced trust in their local society and the influence of their headmate.
All of us were bred to be slaves, good and nongood utility function classes alike.