Humans just can’t seem to stop being dicks

It's interesting, because the work itself seems to have the exact opposite thesis: Humans on average aren't dicks, but inequality and the interests of a few elites with essentially personality disorders the way he frames it, amplify our worst tendencies. For many thousands of years of pre-history, archaeological evidence and anthropological observations clearly show humanity in much more egalitarian societies. The example he uses is of the Khoisan people:

All Goliaths, however, contain the seeds of their own demise, he says: “They are cursed and this is because of inequality.” Inequality does not arise because all people are greedy. They are not, he says. The Khoisan peoples in southern Africa, for example, shared and preserved common lands for thousands of years despite the temptation to grab more.

Instead, it is the few people high in the dark triad who fall into races for resources, arms and status, he says. “Then as elites extract more wealth from the people and the land, they make societies more fragile, leading to infighting, corruption, immiseration of the masses, less healthy people, overexpansion, environmental degradation and poor decision making by a small oligarchy. The hollowed-out shell of a society is eventually cracked asunder by shocks such as disease, war or climate change.”

In general, it's not a very controversial take, that the current (i.e. of the past ~5k years) inequality did not arise as a natural state but became only possible through surplus.