> It has literally determined every aspect of our being. You can't move forward without understanding what got you where you are.

So has physics. Why stop at hunter-gatherers, why not go back to the Big Bang? Would you argue that we need to study astrophysics to deal with obesity?

It's not absurd at all to suggest that evolution is a red herring, any more than it's absurd to suggest that astrophysics is a red herring. Prehistoric archaeology is highly speculative at best. I'm not saying it's unscientific, I'm just saying there are a lot of things about prehistoric societies that we could be very wrong about, due to lack of direct observation and evidence, and thus it would a poor guide for our current and future societies even if we decided to base our behavior on our ancestors (which we shouldn't).

Biologists actually do have to study physics (including the most advanced and theoretical physics) to understand metabolic processes, and their discoveries directly inform medicine, psychology, and other downstream fields like sociology. So that's not as clever of an argument as you seem to think.

No one is saying that we should live exactly like our ancestors.

If you wish to make an apple pie from scratch, you must first invent the universe.