Land exposed by the fallen sealevels (due to glaciation, whatever its cause) would be relatively warmer due to lower altitude, well-watered, full of food, etc, and ideal for maritime cultures. :’)
This may be true, but it would take many, many years for the land to sustain enough food for people to be able to subsist on it and cross the distances. I did a short piece the other day on the Solutrean Hypothesis at the
Bauu Institute. It may be of interest.