The phenomenon that would have made it an estuary on the hominid and homo sapiens timescale is lower sea levels due to ice ages. 40% of the Red Sea is only 10

The phenomenon that would have made it an estuary on the hominid and homo sapiens timescale is lower sea levels due to ice ages. 40% of the Red Sea is only 100 m deep, and during the last major ice age 20kya sea levels were 120 m lower than they are today. https://link.springer.com/referenceworkentry/10.1007%2F978-90-481-2639-2_129#:~:text=The%20Red%20Sea%20proper%20is,is%20shallower%20than%20100%20m https://link.springer.com/referenceworkentry/10.1007%2F978-9....