I've seen it argued that it's also the nature of the education system. That it isn't designed for boys, that men are increasingly absent from teaching, that boy

I've seen it argued that it's also the nature of the education system. That it isn't designed for boys, that men are increasingly absent from teaching, that boys aren't encouraged and supported to the extent that girls are, that the success of sports teams can be a larger concern than making sure the student athletes are getting same level/quality of education, etc. I suspect that there are a ton of factors long before you deal with the issues at the university level.