I mean, you take one look at Greek statues and Roman busts and you realize that people figured how to aim for realism, at least when it came to the human body and faces, over 2000 years ago.
Yet, unlike sculpture, paintings and drawings remained, uh, “immature” for centuries afterwards (to my limited knowledge, it was the Italian Renaissance that started making realistic paintings). Why?
I’m not an expert on the subject, but i didn’t see anyone else mention time as a factor. For a long time humans were simply too busy trying to survive. Once civilizations started coming around along with extremely wealthy and powerful people, then more time for leisure, art, and science came. Some of the extremely wealthy people of the past hired artists, mathematicians, scientists, musicians, etc to just live with them and study full time. The expectation was that they would share their work.
Art and science were largely the domain of the rich and bored for a long time. This wasn’t really conducive of attracting those with talent, just those with the means.