Unlike this flake, Elaine Morgan correctly answered this question in her book The Decent Of Woman.
https://en.wikipedia.org/wiki/The_Descent_of_Woman
Humans have acquired several drastic changes which separate us from our simian ancestors while others of their progeny changed very little. Of necessity, these changes would need to 1) all be related to a single niche we had to fill, and 2) all be related to the survival of hominid ancestor infants.
This flake’s explanation fills neither requirement.
Wow. The Morgan book link I posted is just wrong. Searching for a replacement.....
Elaine Morgan’s book The Decent Of Woman cites several human evolutionary changes which which were all adaptations to a marine environment.
1. Upright gait.
2. No fur.
3. Unique downward-turned nostrils.
4. Continuously growing head hair in women.
5. Infant survivability in water.
6. Infant finger grip.
7. Female subcutaneous fat layer.
8. Extra-muscular breasts.
While men were off chasing small animals surviving women were evading predators by running into the surf with their infants.