I have been looking at arts (drawings, sculptures) from different archeological periods (40000BC up to now). A pattern that I have picked up consistently when looking at arts from these periods is that the accuracy and fidelity of such arts is not good and most arts seem to be very abstract with not that much details. I have personally never seen any arts that dates back to around 10000-15000BC and before that which do not look realistic by any means and contain lots of details, to my observation. I am by no means an artist or art historian but to me, it is obvious that humans could not draw detailed arts (e.g. sculptures, drawings) until around 4000BC or so. This conclusion could be coming from the fact that I've never been into arts and I've not spent a lot of time looking for such arts.
So I wonder what's people's thoughts on why this is the case? Could this be because simply humans did not have good tools to draw things more accurately or they had not developed the cognitive ability enough to pay attention to such details? Or could it be because they simply did not want to be accurate purposefully considered arts to not that serious for some reason? I'm asking this because I've seen lots of paintings or sculptures in which things like a human body is drawn with just a couple of connected lines or the sculpture of human body (here --> 1) which does not resemble a real human body in any way. In many such paintings or sculptures I've noticed that most details (e.g. eyes, breasts, muscles) are missing or have been drawn/sculpted weirdly; I've noticed this pattern in prehistoric arts for both humans, [animals] (here --> 2, 3) and other things.
Or could this inaccuracies/infidelities be a result of not having peace as human species were like preys and had to constantly look for food or run away from wild animals or other humans? It's possible that if they had piece they could have spent more time on art and made nicer things, right?