"Why on earth would you ever encourage ANYONE to line up for work in a coal mine?"
Do you hear anyone complaining that girls are under-represented in coal mines like they do about high paying low physical exertion jobs?
I'm pretty sure that's the analogy here. do you not understand analogies? it's used to compare two things that are similar but different so to maximize the point in the comparison that they both share but might be overlooked. In this case it's feminists demanding partial equality in jobs but masquerading their complaint as demanding full equality in jobs.