That's interesting Fleetsum. I think a lot of people who haven't really thought it through much first and foremost "know" that a trans person is a victimised minority whi=o can't help what they "are", exactly along the lines of the homosexual people they have traditionally been lumped in with. It would be bigoted ijn the extreme to have anything negative to say, because that's how it works with gayness (totally reasonably in the case of gayness, because it makes no demands on anyone else, other than equality and respect).
That means they are required to believe that TWAW and TMAM because that is how they say they feel (the vocal activist ones anyway). It doesn't matter that according to science and common sense that's not possible - after all the establishment, science and common sense have been wrong before and it's better (not to mention way cooler and virtue-signalling heaven) to be on the side of the underdog and stick it to the traditional bigots.
Then when they get asked to define women and men, address issues of women's sex-based protections etc, they are a bit stumped. It's really hard for them to go there as it requires a leap back into rational thought. Falling back on "you're a bigot because you dare to question being nice to a poor oppressed minority" is so much easier, not just in terms of cognitive dissonance, but in terms of not losing your friends and woke approval.
I have a sibling who is "non-binary" and deeply involved in the whole scene. For them to question it is even harder - it would be their whole world exposed as the emperor's new clothes, their social life, relationship and sense of self, which they have always sought through one kind of "special identity" after another, down the pan. They are so massively invested in this empirically impossible belief.
To me it very much is like a religion, and I'd be OK with respecting someone's empirically unsupported belief in the same way as I respect religious people - if it wasn't threatening to lead to legal changes that massively endanger so many people and impact negatively on me. But the situation at the moment (though I am confident it's changing) is that so many people are terrified to question it. It's like a religion that has taken over the state and so many people either swallow it, or know they have to say they do.