Why didn’t you elbow him over? Or say, a bit loudly, “Excuse me, sir. I know these seats are small, but you’re taking up half of mine and I paid for the whole thing. You need to scoot over.”
As for the gender thing, please. My husband and son are both over six feet tall and always have to pay extra for the seats with more leg room. Is that fair? I was on a flight in Europe where a man who was at least 6’ 3’’ had to sit sideways to fit in the seat. Businesses class was empty but the flight attendants wouldn’t let him move up. Obese people are often required to pay double for two seats regardless of gender.
I agree, the airlines are screwing us. But let’s not pretend women are a specific target. That’s just silly.