Oh, sure, we probably agree. A distressing amount of people have really bad takes on sex, sex education, gender, history, relationships.. a lot of things, really. Conservatives especially have egregiously bad views.

I remember when I first saw This Film Is Not Yet Rated, and I talked about it with some coworkers. An older woman and a younger woman who sat next to me in the office. Both of them 100% felt that they'd rather their kid watch a movie where people's heads got blown off than one where someone got head. I don't remember their exact argument (this was many years ago), but I'm pretty sure it was such an axiomatic belief for them it was difficult to articulate why.

I'm not sure what you mean. Parents are ideally involved in raising their children, but there's no guarantee they'll be involved, good at teaching, teaching anything true, alive, or anything. Public education is important.