"Gender critical" is the anti-trans movement. The reason you can't tell their true position is the usual one: they daren't say "we want to eradicate trans people" in public, so they take the "just asking questions" route.

I feel that the trans community has largely been forced into defending "trans women are women" (TWAW), even if it has holes as a philosophical argument, because they need to fight the transphobic "trans women are men" rhetoric and downstream policy decisions. How can someone live as a woman without constant risk of being outed? They need an "F" on their passport and to use the women's toilets, etc. without having a constant risk of being "caught", because that ends badly.