The evidence of better health is new to me but as you and others pointed out that it exists I need to look into that more. However, given what Harari says about hunter gatherer tribes remaining today that have up to 50% of their men killed by violence, mostly tribal warfare, I fail to see how it can be said this lifestyle has a higher quality of life. Some have noted that hunter gatherers have more leisure. Not sure that has equated to better life, particularly if one faces a 50% chance of dying as a young man.