We need to start considering there may have been fairly advanced pre-Neolithic civilizations. Perhaps evidence of them was destroyed during the last ice age?
I have been wondering what was in the area now underwater after the sea level rose when the last Ice Age was over. It won’t surprise me if there were significant civilizations there, predating Egypt and Sumer.
Denisovan and Neanderthal quite possible were pushed over the edge by the eruption of that super volcano the cauldera of which is associated with Vesuvius. IIRC it erupted about that age, and those two peoples were populating areas directly in the fallout zone while us regular folks were more spread about. Would have been approximately 1.5-2 essentially summer-less seasons too...
If a previous advanced civilization existed prior to the Ice Age and built primarily with glass and copper, the ice melt runoff would have scoured it to bedrock, and time would have destroyed most if not all artifacts; plus. since human cities and population centers tend to be on ocean shores and at river mouths, they would now be under hundreds of feet of sea water and covered by more hundreds of feet of silt.
There is reason to believe that before the Old Kingdom of Egypt was established a group called the “Westerners” lived and built on what is now the Nile Delta, however all remains are buried by 3,000 years or more of silt - several hundred feet down.
The Ice Age ended 5,000 years or more before the “Westerners” built.