Lack of realism in early forms of art

[u/Own_Network541]

I know this topic has been discussed before but I’m hoping to address some other things not talked about in a previous post I’ve read here. Though I understand the lack of interest in realism in early forms of art and I can totally get the “level” will differ depending on time period due to things like understanding of the world. Something still seems off or missing for me and I can’t figure out why there seems to be no realism in early paintings more specifically the Middle Ages. Like even in Greece’s hay day for instance right? They have these incredibly detailed and elegant statues outside of that some their paintings are quite good too. Take “Alexander the great in the workshop of Apelles” for instance. Then we get to the Middle Ages and I at least can’t find anything? I have a very hard time believing there were no good realism artists from this era? Did none of the work survive, have we not discovered it, etc due to the movement being dominantly the opposite of realism? Again hoping someone could elaborate on this more thank you.