Some combination of much higher birth rates, ecological destruction, and centralized governments among other factors made agricultural societies more successful in the Darwinian sense.
You see this in the history of the Europeans vs Plains Indians. Very few military successes for the Europeans, but ultimately the Europeans displaced the original inhabitants of the Great Plains almost entirely. The Comanches never "chose" to become agricultural. They were forcefully pushed out over generations.
That piece also seems to be somewhat unspecific on what exactly "limiting the population" entails; after all, infanticide, a lack of medical care of any kind, and outright murder are no less available to a farming society, if you really are arguing for such a solution to inequality.
Without domestication or preservation/storage, hunting and foraging may take a while and be unreliable.