Swords, crucifixions, spears, arrows, were more than sufficient for ages. The populations were smaller, the portion of the dead were also smaller. Advances in this or that occur on a regular basis and permeate the population, such as a new hoe, in flux of silk, at a lower cost, an abundance of corn or wheat, that lowers the price, a new building material or way of building. Yes, these changes take time, often generations. Even the Roman Empire eventually made everyone a citizen, it was just more practical, and it came with, for the time, tremendous privileges.

Absolute monarchs were eventually checked, the lucky became Constitutional ones, the other’s lost their heads. Social progress progresses almost strictly based on material abundance. After Rome fell, it took over a thousand years to return to that. Only when there is plenty to go around do things improve easily. Such as after the Black Death killed up to 25 percent of Europe, more in some places than others, the peasants labor was worth more, in England a new college for lawyers was needed, upward mobility became a possibility. Add trade, the Renaissance, learning, and the average person’s life improves without catastrophes. Yes, it is not as quick as one might like, but there is a lot to be said for keeping things stable for both the family and the children, so they can grow up without being terrorized.

Your rejoinder to my argument on slavery, at the end, simply proves that things can be improved over time, without mass slaughter.