Aight, you asked multiple questions, so you’re going to get some strange answers, possibly including this one.

To your title question, the only time I’ve heard anyone say that, they were being a douche. My response online is mostly of the “down vote, report if appropriate, and move on” variety.

In meat space, my response is usually either an eye roll and walking off, or a “fucking moron” and walking off.

I have big dude privilege in meat space, and roll well armed, so have no need to pretend to be nice to douche nozzles spewing bullshit.

The other questions are harder.

1: for a given value of factual, sure, I guess. But it’s using imprecise language that’s been weaponized, so I would be dubious of someone stating it until there was more context. “Biological” isn’t as definitive and limited in usages as to be without question in that context.

2: don’t matter. If a guy says he’s a guy, he’s a guy. If a gal says she’s a gal, she’s a gal. End of fucking story, and I will gladly tell anyone fucking with my trans homies that they’re a fucking moron and be willing to either walk off, or fuck them up if they insist. IDGAF about sometimes XY or XX status, or any of the other possible combinations (remember when I said “Biological” isn’t that useful or definitive? Yeah, biology ain’t a binary). I care about the person’s expressed self. It’s about basic human decency and respect.

3: I wouldn’t respond logically. It doesn’t merit any effort on my part. I’m not in the business of convincing anyone that everyone has human rights, should have equal acces to all civil rights, or that someone else’s gender is none of their fucking business. It isn’t about logic. Anyone at this point trying to frame gender as some kind of science debate is a douche and can go fuck themselves. The debate at this point has nothing to do with “biology”. It’s about human rights. And yes, I will fight on that hill.

4: it would only contradict if the person trying to bring “biology” into a conversation is being a douche instead of just missing the point. I don’t automatically assume a person trying to frame the subject in those terms is acting with malice. So they may not be contradicting the fact that trans women are women. They may just be exploring the language of transness in an attempt to better understand the matter. And that’s okay. It isn’t a built in part of language, so everyone has to absorb the concepts over time.

Alas, assholes and morons use that language to denigrate trans people. So I also can’t assume someone isn’t doing so. I have to wait for context, or be proactive in stating that I ain’t putting up with bigotry, so if that’s where they’re going, it won’t end well.

Me? The debate is over. What’s still in play is people finding their path to internalizing the subject. We don’t get to debate what is a fundamental human experience. Trans people exist. It isn’t imaginary on their part, it isn’t bad parenting, it isn’t trauma. They’re trans, and that’s it.