Frequently asserted, but not really well substantiated. Plenty of new (or previously) ignored archeological and anthropological evidence that humans moved back and forth fairly seamlessly between hunting, gathering and cultivating in many differents part of the world.
You sound like the kind of person who would have somehow managed to read "The Dawn of Everything" by Graeber & Wengrow, but apparently either did not or for some reason disagree with one of their fundamental conclusions.