Also, too, the higher echelons on most occupations are mainly men. Partly this is experience - women’s equality hasn’t been around long for many professions. Partly it is the interruptions and less dedication (aka “a life”) mentioned above for women - they are less defined by what their work is, than by things like “being a mother”, while nobody says of men, “what defines his life? He’s a father.” Possibly sexist, but socially significant.
there’s also gender interests or abilities. The computer field is realtively new - there should be no gender bias. But, the overwhelming number of persons interested in working with computers and delving into the details are men. OTOH, life sciences, IIRC in Canada somewhere starting around 1990 or so the majority of medical school students were women. There’s an observation somewhere about nurturing vs. mechnics.
Finally, there’s the “elbows” phenomenon. It’s said men have sharper elbows; they are more willing to push their way up, push others out of the way, promote their own interest.
Also men, who decide who to promote, are “threatened” by smart or competent women. But sadly, maybe it’s the number of hours, maybe it’s the brain makeup, maybe it’s the lack of distractions like mothering, but most men throw themselves into their occupation or recereational passtime to a greater extent than women. they get the promotions, they higher pay, the recognition, the awards.
But when it comes to basic jobs - from clerk at the store to school teacher - pay rates are generallys set and accepted in a gender-neutral way. Just, thanks to “elbows” the school teachers are all paid the same but more men seem to be principals.