I can’t speak for Apidistra, but most terfs would consider him to be a “confused lesbian” who has tragically damaged his female body with unnatural chemicals. His best bet would be to get off the testosterone and find a cute skirt so that women aren’t (as) upset when he shows up in the female-bodied space he belongs in.
Really, that’s what most terf rhetoric boils down to, which is that everyone (but men especially) needs to be forced to express the gender identity of the genitals they were born with. That way, men are always performatively masculine and women are always performatively feminine and there’s never any question what kind of genitals anyone has. By coincidence, this happens to be the arrangement that Patriarchy has enforced for centuries. Funny how that works.