besides, ancestral hunter-gatherers often got plenty more calories than ancestral peasant farmers, despite coming earlier: which one is our "ancestral environment" here?

This bears repeating. Also keep in mind, many people with western European ancestry have a much higher threshold for diabetes, due to that ancestry's post-agricultural dietary habits. After several thousand years, agriculture becomes part of the evolutionary environment.

(In the long view, I often stop and ponder whose ancestral environment and population we are, and how the cultural and environmental choices we're making today will shape the genetic predispositions of our 61st century descendants.)