This is an unfair comparison. Maj conference D1 is at least 5.5, and yes, they would crush any 4.0 male. D3 is 5.0 according to the self-rating guidelines.
Here is a more representative video of D3 women.
The level is A LOT closer to men's 4.0, although still a little better than almost all mens 4.0 rec tennis.
EDIT: Watching Ms Greenberg is mesmerizing (@2:55...).