Despite the fact that I'd like their premise to be true, and that it seems there is truth to the idea that "primitive" societies in the past were more complex and interactive than we once thought, the authors have cherry picked data and built a variety of straw men to dismantle in order to recklessly extrapolate and generalize to make an argument about what they would like society to be like.

Read this book with a lot of caution, and do some other reading of both the specific examples they discuss, and also of the general context and premises that they put forward. They present a lot of information and it is easy to take them at their word if you have no knowledge of these or related fields.