The question I think is, is that "good reason" a reason that was relevant as our brains were evolving millions of years ago, but is irrelevant now? Our brains

The question I think is, is that "good reason" a reason that was relevant as our brains were evolving millions of years ago, but is irrelevant now? Our brains evolved in a way which maximized reproductive potential, and while having strong cognitive abilities was clearly favored to an extent, there was a constant tradeoff between larger brains and food/energy input. Now that we don't have the same critical food shortages, we can set our own objective functions. Ex, now most people would probably choose a brain with +50 iq points which required an extra 1000 kcals a day, but a few tens of thousands of years ago, those requirements would probably have been fatal...