I'd say the probability of an imminent maternity leave for a 22-year-old with a new job as a lab manager in a university is pretty damn small
I'm too lazy to search for data on education-based cohorts, but only 57.5% of US women are childless by the age of 25.
The source I found showed a really drastic difference between college-educated and not-college-educated women.
I remember seeing a talk of the concept of privilege show up in the discussion thread on contrarian views.
Some discussion got started from "Feminism is a good thing. Privilege is real."
This is an article that presents some of those ideas in a way that might be approachable for LW.
http://curt-rice.com/quotas-microaggression-and-meritocracy/
One of the ideas I take out of this is that these issues can be examined as the result of unconscious cognitive bias. IE sexism isn't the result of any conscious thought, but can be the result as a failure mode where we don't rationality correctly in these social situations.
Of course a broad view of these issues exist, and many people have different ways of looking at these issues, but I think it would be good to focus on the case presented in this article rather than your other associations.