I notice that some anthropologist believe all humans were egalitarian in the past, and others believe inequality was more common they we currently we think with hunter gathers.
This seems to along with anthropologist using modern hunter gathers as way to look at the past which is now considered not a best practice from what I read. Which this influenced the egalitarian hunter gathers idea even more.
Edit: I did a quick re-read and it seems like most societies that were hunting and gathering societies in recent history are becoming increasingly settled due in large part to the intrusion of global economies and agricultural practices in to more and more marginal land. The !Kung people who have been protrayed as the "model" hunting and gathering society are now increasingly settled as a result of the expansion of agriculture and the intrusion of cattle ranching in to their traditional lands.