Modern humans have existed for something like 100,000 years give or take a few tens of thousands, and yet we only started building anything particularly innovative in the last ~10,000 or so. So we spent 90% of our species' history doing very little in the way of cognitively challenging innovation.

I wonder if this might not be the reason. Some have observed that hunter-gatherers often had better nutrition and were healthier than at least early civilized humans, but maybe they also lived under a perpetual cloud of fear about the next famine, raid, or plague. Maybe that basically shut down their capacity for higher cognition. Maybe they didn't have any time to sit down and think and do so free of concern about the future.