I mean, the bronze age took place during class society, and it wasn’t even that long ago compared to the time anatomical humans have existed. As for whether past cruelty would make modern people look like saints. If we’re talking about Joe right across the street or something, sure, why not. But we have had non stop bombings, coups, invasions, sanctions and so on for a while, I consider modern capitalists to be more cruel as a class than many kings of old.