I also wish sexual education was taught more. I only had a short session in school about STIs, and that was it.
Some people may say that young people have strong hormones, so sexual education just wouldn't work. I feel that's like saying "Don't teach kids to play around windows because that won't work." Of course parents tell their kids to not play around windows, though some kids unfortunately still fall out of them. If people taught teens the dangers of sex (like STIs, sexual cannibalism, prostitution, and etc) then I feel that teens would learn to fear sex like a window.
Because the reality is that teens learn eventually, and sometimes through the worst ways like paying money to a prostitute for Herpes or being robbed after a one-night stand. If nobody teaches a teen that sex is dangerous, bad, or should be avoided; then what would protect a teen from another teen who says "sex isn't bad" or "sexual acts are bad but I'm not performing a sexual act." Some parents might not need to teach about STIs because their kid would obey them: "My parent told me that sex is sinful, so don't touch me." Yet a sinful teen can be like a snake in a garden and will try many different ways to fool another teen.
In my society, I feel that females are given more informal sexual education than males, though the education is probably mostly about pregnancy or rape and not about other broader issues like STIs. My own sexual education began with pregnancy and rape, but I realized that those were mostly dangers for women and did not really apply to or threaten me.
In my society, it seems like males make a lot more sexual mistakes than females. It's as if men are societally allowed to be sexual or to make sexual mistakes, and I don't like my society much for endangering males like that. Some societies might be afraid to thoroughly teach sexual education because such might make people fear sex. In fact, I've somewhat educated myself to that extend and would rather adopt than have sex.
There are some parents who do formally teach kids about the dangers of sex, including some broad understanding of sex or sexual actions. The Abstinence approach is not bad and I actually love it because it 100% guarantees no STIs unlike condoms. When I was reading about diseases from government websites, some of those websites included abstinence as an STI prevention method. But again, a teen would need to be quite devote and faithful because some sinful teens are very good at tricking people. The tricks are sometimes even an art or sport, and some societies encourage or protect them.
Some kids are fortunate enough to be taught through rejection, but females are not responsible for sexual education. A woman can sooner make a false rape accusation than she just tells a man to stop following her. And some people even take advantage or prey on other people who are not sexually educated, like exchanging Syphilis for money. There are even some people who'd refuse to disclose their herpes status before sex: the lack of education can be endangering. If teens are not educated about sex, then criminals will take the role and proactively educate teens through inappropriate content, sexual street music, and etc. There are laws protecting teens from such sexual misguidance but criminals don't care, especially in bad neighborhoods.
My dad left when I was a kid, so I had to learn about the dangers of sex by myself. Before I formally educated myself, I learned the hard way and made many mistakes. I'm thankful that I wasn't too foolish: most of my sexuality was verbally communicated.