I don't mean this to sound overly harsh, but I think treating this situation as some sort of mystery is part of the problem.
All that one really needs to do to understand why the field is unwelcoming to women is to start listening to women.
All that one really needs to do to understand why the field is unwelcoming to women is to start listening to women.
I imagine that is part of it.
Trivialization of women's issues is a different monster.