If you re-read my post, I am pretty sure I didn't say that men can't get sexually assaulted, just that it's something that is common for women to worry about (when they meet somebody new). Meanwhile when a dude goes on a first date, that is rarely a thought in his head (that the date will lead to sexual assault or some other form of violence)
Sexual assault and rape does affect men as well of course, and the stigma of men not seeking help when it happens IS a problem. That's IMO why being told "to man up" does not help, whether it's in the context of an athletic competition or something more serious. When boys are told things like that it will make a huge impression on them, and they'll grow up into people who do not seek help when they face sexual assault or violence (from any gender). That's why I'm fiercely against gender roles of any kind in our society. Many of them seem harmless, but I disagree. The longer we stick to these outdated gender roles, the more we'll continue having problems in society that don't have to exist. Abolishing gender roles will help both men, women, and those who do not self-identify as either.
Of course getting rid of gender roles will not be an overnight project, it will take generations. They aren't going anytime soon. So in the meantime we need temporary solutions for these issues. And in some cases they exist, you just have to find them. My work for instance offers mental health therapy for free, you just have to figure out where to go and where to sign up. I made use of this earlier this year, before the pandemic hit. I ended up in a room with a professional and I unloaded all my concerns on her. It really helped, even though she didn't really do much. But she listened and that really helped me. It really helped just talking about it. Most universities will have such support programs for students as well.