This is anecdotal, but in my experience girls just genuinely aren't given the opportunities to engage in STEM or any sort of challenging degrees for that matter. The girls I knew all wanted to get good grades and they did. It's really annoying when girls are not given equal opportunity to succeed in STEM so much so that they essentially have an academic handicap, while boys still get given these opportunities. I'd bitch about it too if I were female
Label: no hate