Because so much water was caught up in the vast, mile or more thick ice sheets, the sea level was almost 400 fet lower than it is today. There was no Bering Sea. It was land. There was no ice sheet over this area as it was too dry. So Northern Siberia and China to Alaska was one huge treeless tundra.
The Cordilleran North American Ice Sheet started towards Eastern Alaska down through California and Colorado. The Laurentian North American Ice Sheet was the biggest, and went from most of Canada to Eastern Dakota all the way to almost the Ohio river valley to New York and up the coast to Newfoundland.
The earliest Americans came from Asia in boats along the Pacific coast all the way down to South America. However, since the sea level rose back up hundreds of feet after all the ice melted and drowned out these sites and well never find them. But some fishing vessels dragging trawl nets along the Pacific coast have found spearpoints, arrow heads and other man made objects in certain areas (Coastal British Columbia, Washington State, California and Ecuador.)
Atlas, that’s basically my same thought, but from Europe. The earliest points are much more like what is found in France than in Asia. And you are right, the earliest sites are under water, but don’t try to have that conversation with a global warmist;)