I’ve read Wrangham, Haw, Girard, Fields and others, but for the sake of brevity I chose one of many facets.
The author states that modern life is stressful and not normal. Personally i rather walk into an air-conditioned market than worry if my arrow hits home after sweating in ambush all day just to eat.
I think it was more normal to work hard, experience competition, and feel stresses of survival for most of human kinds existence, and that only now in the last few hundred years have we had it truly easy, even with poor agricultural returns.