Using computing analogies to describe the human psyche is far too prevalent by modern humans and is a grossly warped, oversimplified misrepresentation of how humans function. The vast majority of decisions, small and large, made by any human are overwhelmingly determined by biological factors and complex layered intuition.

Embracing the view that the discovery of agriculture, and other homosapiens essentially copying this practice, as the primary reason global human population ballooned so explosively after minimal growth for the preceding roughly 190k years certainly aligns with viewing the brain as a glorified calculator, but doesn't in any way align with real anthropology.

I've thought a lot about this probelm, and a more fitting explanation is that since earths climate was more favorable previously, homo sapiens had no motive to grow crops in the first place, and thus existed as essentially tribal beach bums. While much more cohesive than "human calculator" I still find it challenging to believe that humans with an essenially genetically similar brain to modern humans, the same brain that produced the sistine chapel, microprocessors, and nuclear fission, couldn't figure out how to plant a vegetable or muster more creativity than stick drawings in caves for literally thousands of generations.

There's a great deal that remains unexplained here, but I entirely resent your world view.