despite being widely known and discussed

I really think you’re taking the “online world” too seriously here. Almost nobody I know in real life could explain to me a distinction between gender/sex. Except of course the friends I made studying psych at uni. Everyone else just think gender means sex. It seems pretty obvious this isn’t majority knowledge.

They are making a claim about science that I falsify right in front of them. Then they baselessly deny the evidence.

Which evidence? That subsections of scientific enquiry have been using the word gender to mean “X” and it’s well established in those fields? That isn’t data that will convince anyone, it’s simply agreed upon language. If someone says “that begs the question…”, and I say “no you’re using that wrong, in philosophy that means…“ do you think thats actually convincing to anyone? It means next to nothing.

You simply claiming that a large part of social science (and graduates from such leaking into government wnd social media) use the word gender differently to sex, means nothing to someone who has the belief that gender is exactly the same concept as sex.

I mean, you are free to keep assuming the entire world knows about this relatively niche area of research. I just don’t think it’s gonna help you do anything except rack up internet points from people who already agree with you. It’d be just as fruitful travelling the internet reminding people that “pedophilia” simply means attraction to pre-pubescent children, and that its neither an act, nor a crime, nor applicable to any situation involving anyone of puberty age or older. OR assuming that everyone should know that enforced monogamy doesn’t mean physically forcing people into relationships.