There is no ambiguity at all about most people’s sex.
Continuing to repeat this adds nothing to the discussion.

Oh, so now all of a sudden
you care whether claims add anything to the discussion, do you?
Which side are you referring to?
Seanie and I are both on the side of women who want a male free place for personal business, under certain circumstances.
...
It's really about making the trans disappear, not about putting them in the "right" bathroom.
Asserting this adds nothing to the discussion.
I don’t think any men they should be using facilities reserved for women.
...
(Yeah, I know, the real "answer" is that they disappear.)
Continuing to repeat this adds nothing to the discussion.
Well, does the existence of intersexed people tell us what course of action produces the least harm? Does lying about whether Parliament meant biological sex produce the least harm? Does lying about whether transwomen are women produce the least harm? I'm skeptical about whether make-believe is an effective harm-reduction strategy.
... Of course the real position is expressed by P2025--that they cease to exist in society.
Continuing to repeat this adds nothing to the discussion.
You are not stupid, so you cannot possibly believe that making up the most shameful motive you can think of and condescendingly explaining to your opponent that that's his real reason
is an effective way to persuade him. He knows his own motives, goals and intentions far better than you do. So you must know that when he hears you he's going to know perfectly well that you're just trumping up an ad hominem argument. So who exactly are you trying to convince when you tell us "the real position" is that they cease to exist in society? The gender ideologues on your side -- are you virtue signaling? Lurkers -- are you well-poisoning? Yourself -- are you giving yourself permission to dismiss our actual arguments even though you haven't refuted them?
Making up a discreditable motive is all too easy. Here, I'll do it back to you. We all know why you care about this issue. Single-sex bathrooms are awkward for your sister-in-law, because she's mannish-looking so other women keep objecting to her using the women's room. It's distressing to her, and she's family, and you care about her. And distress to one woman you know and care about carries more weight on your scales of cost/benefit analysis than distress to a hundred million women you don't know and don't care about.
I'll bet you don't find that a persuasive argument. Think about that the next time you're tempted to tell us we just want trans people to cease to exist.