The statement is a motte and bailey. "Trans women are women" meaning "this person wants to wear a dress so you should accept their social identity" is the motte. "Trans women are women" meaning "this person with the advantage of male puberty must be allowed to punch women in the face in boxing or else you're transphobic" is the bailey.
Your analogy fails because there aren't biological differences between people of different faiths. There are real biological differences between males and females, now detectable to the earliest life stages. Surgery and hormones won't change that, so we should drop the "Trans women are women" rhetoric, because the statement is false. It also enables bad behavior like trying to force lesbians to like dick, lest they be called transphobic.
It would be much more productive to come up with a new pithy statement meaning "be nice to people even if you think they're weird".
Note that these are both social issues, not biological issues, and it's possible to have different opinions about the two. There's certainly no biological imperative to have separate sports for men and women; that's simply a social convention. If we look only at men, those who are taller typically have a huge athletic advantage over those who are shorter. Why don't we have separate pro basketball leagues for tall guys and short guys? Even the "shorter" NBA players, usually guards, are almost always taller than the average male. As a shorter than average male myself, I'm dwarfed not only by NBA players but also by WNBA players. Where do I get my fair shot? ;-)
> Your analogy fails because there aren't biological differences between people of different faiths.
As I already said in my previous comment, this is a social issue, not a biological issue. I also elaborated on this in another comment in this same thread: https://news.ycombinator.com/item?id=42674247
> It also enables bad behavior like trying to force lesbians to like dick, lest they be called transphobic.
I have no idea what you're talking about or where you're getting this stuff.
> The biological issue is that men competing against women will cause very real biological injuries.
Uh... this is quite a bizarre statement, given that you previously brought up boxing, in which the entire point is to cause very real biological injuries to your opponent. If you hadn't noticed, in all sports, men competing against men causes very real biological injuries, as does women competing against women.
> Saying that women shouldn't get to compete in the Olympics is fine, you should just be honest about it.
I wasn't making any suggestions, merely pointing out that the current divisions are arbitrary social conventions that could be changed. I honestly have no strong opinions about sporting rules, and I was joking about the need for a basketball league to accommodate me. I've played tennis but not basketball.
> I admire your innocence. Search for "genital preference transphobic" or the like to see an example
You can always find examples of any opinion in the world on any subject, but if they're not commonly propounded or representative of the public debate, then they're largely irrelevant. You can't validly repudiate a position by pointing out the most extreme advocates of the position, otherwise you would repudiate every position.
[EDIT:] It was probably a mistake for me to get sidetracked arguing about sports. The weirdest thing about your "motte and bailey" argument is the implication that the worst thing about acknowledging the self-identity of transgender women would be its effect on sporting competition. Whereas transgender people themselves appear to be much more worried about things like violence against them, discrimination against them in the workplace, housing, and health care, and general social disrespect, refusal to accept their very existence. I think that sports is largely a red herring.
Your analogy fails because there aren't biological differences between people of different faiths. There are real biological differences between males and females, now detectable to the earliest life stages. Surgery and hormones won't change that, so we should drop the "Trans women are women" rhetoric, because the statement is false. It also enables bad behavior like trying to force lesbians to like dick, lest they be called transphobic.
It would be much more productive to come up with a new pithy statement meaning "be nice to people even if you think they're weird".