You're probably too young to remember it, but I grew up at a time when women had to take legal action to get those kinds of jobs. I recall one woman that tried to get a job operating a jackhammer. Small thing she was. Her dad taught her how to use it, and by the time she was 20, she could hold her own against a Hippo Harry.
While you use the college liberal for this meme, not very many conservative college men would want those jobs, either, unless they were in management positions.