At 21 I was trying to persuade the Marines to ditch their single sex requirements so that I could prove women were capable of passing the course.
They were too fraidy.
So I joined a different branch of the military and got given a secondary duty of babysitting coordinator, by virtue of my gender. And when I whupped the men's arses in physical training I was accused of cheating. And I had to leave formal events at a particular time in the evening, so that the menfolk could smoke cigars and play rugby in the bar. I'm not 110, this was in the 1990's.
That said, when I eventually left and went back to uni as a mature student, it was chock full of 21yos who believed that the world was an equal place. Even the women. I nearly died of shock and gave a huge lecture to the utter bemusement of the instructor who was attempting to broach a discussion about gender equality.
So I think it depends a lot on how much actual honest to goodness sex based discrimination you have been faced with. If you have never tried to do anything other than toe a gender- scribed line, then life is going to look pretty rosy.
Of course, most women get it writ large with the baby thang.
I didn't give a rat's arse about the theory when I was 21. I was more concerned with the reality.