Again, this seems to be a fairly new belief.
First it was "brain sex".
Then it was "hormonal sex" which I think started doing the rounds a couple of years ago.
Now they're saying their "tiddy skittles" 🤢 (sorry) are literally, in the normal usage of that word, transforming their whole biological makeup.
And there's always handwaving about "science" and what we now know, but I genuinely think this is all activists bumping gums on various forums that then finds its way uncritically into tribunal hearings and mainstream media.
We are in Bizarro World.