Yeah, it's "the treachery of images" logic where the fact that there is a gap between the symbolic nature of the word "man" or "woman", and the physical reality they describe is meant to blow your mind. Lame philosophy on the level of a weed revelation. The underlying reality still exists, and is the thing that all our social conventions are built around. Even if you accepted troon logic, the logical endpoint of that is that being a woman is meaningless, and that we should focus on the package of physical traits as the relevant factor in how we treat people. Why should woman have sex segregated spaces, if woman has no definition? Why not segregate space by karyotype then?
They want it both ways, where the limits of language prevent true connection between an object and its name, while also maintaining all the social norms of womanhood, despite those not making sense if womanhood isn't defined by physical characteristics.