DaMoshe:
“The vast majority of students don’t have relationships with the opposite gender.”
The elementary/high school you send to is the minority of RWMO. The large majority of MO students go to LWMO schools, where the schools are co-ed and the large majority of students have cross-gender friendships and/or boy/girlfriends. Especially starting in high school and even more especially after graduating high school.
Additionally, in Yeshivish, Lakewood and Chasidish schools, having a boy/girlfriend is virtually non-existent.
“We’ve had times where the Rebbetzin went over to someone to ask her to walk out until she changed, or covered up a bit. We’ve had divorced women who no longer wanted to cover their hair who were told that’s not allowed in the shul.”
You see, even in your RWMO shul you have this problem. Forget about what goes on in LWMO shuls, which constitute the large majority of where self-identified MO people daven. (Assuming they even go to shul; MO rabbis have been widely reporting over the last few years that a very significant percentage of young MO adults no longer come to shul.)
In Yeshivish/Lakewood/Chasidish shuls, it is virtually unheard of that women need to be told to “cover up” or go home and change. Or for divorced women to have the audacity to come with their hair uncovered, for that matter.
“R’ Moshe held it only needed to be 5 feet tall.”
Wrong. Rav Moshe held, B’DIEVED, it must be at least 18 tefachim (66″). And Rav Moshe writes that the mechitza is D’Oraisa. Rav Moshe writes that one is obligated to protest with all his might against a mechitza which is less than 18 tefachim. It’s assur to daven there, even if you won’t otherwise be able to daven with any minyan.