It would not matter how many K-12 same sex Yeshivos are opened in OOT communities. Non-observant Jews will not send their children. The exception is in cities with terrible public schools which are majority minority (in the US that means Black and Hispanic).
Non-observant Jews who fled to suburbs after integration in the 1960s chose communities with excellent public school systems that prepare their children for top colleges and universities and careers in the secular world.
They have no interest in private Jewish education that is same sex and vastly inferior in terms of secular education.
They have no interest in a self imposed Ghetto…that’s why they live OOT.
This does not apply to the observant population.
Written by someone who lives OOT in a small suburban community, who moved from the deteriorating city he grew up in by choice. Who raised his family in a one frum shul town and drove the kids to yeshiva in the nearby city and sent them away for high school, mesifta and seminary…then to college and Law School.
95% of the Jews in my town are ‘non-orthodox’ they have no interest in private Jewish schools.
BTW>>>the description ‘non-observant’ is pejorative and offensive. Non-frum or non-orthodox Jews may observe the norms/rules of Judaism as laid out by their branch of Judaism (Conservative, Reform). It may not be what this community considers Torah Judaism, but they are Jews (unless following Reform Patrilinear determination). When the shoah arrived, they didn’t check to see if you were frum before requiring you to wear a Yellow star, live in a ghetto or worse.