There’s a very important thing that needs to be at least recognized in this discussion:
philosophical point of view.
The more I’ve looked into our history, the more aware I have become, that “progress” is a point of view issue, and is actually being fought over rather constantly.
In addition, HUMAN progress, that is, the development of humans as creatures, is entirely distinct from TECHNOLOGICAL progress. It is actually NOT KNOWN whether or not there has been any significant change in humans as a reasoning creature, over the very great deal of time that it took to go from pointed sticks to iphones.
In addition, TECHNOLOGICAL ADVANCE, needs to be looked at a LOT more carefully, if you want to discuss it in this particular context. And more than one facet of it needs to be noted. Most people probably realize on some level, that technological advances are interdependent. Even if the first caveman imagined being able to sit on a mechanical vehicle and travel, he wouldn’t have been able to even BEGIN to follow through on such, until thousands of other problems and inventions were developed first. That’s fairly obvious. What’s less obvious, perhaps, is that once an advance DOES occur, human society is often irrevocably changed by it, and not always for the best.
By the way, my very simple answer to the title question is:
No we don’t know “what happened to man,” and further, chances are, NOTHING did. I believe we are as we were ten thousand, even a hundred thousand years ago. I know for sure, that there have been no changes in “man,” in all of recorded history. And all that we have discovered through archaeological research of the times before that, strongly suggests that there were no significant changes for a VERY long time before we started incessantly writing things down.
Flowers in the graves of Neanderthals, prove that.