I think the challenge it offers is to the idea that 'being trans' is a innate thing that is the same across the population. There is quite clearly a group of unstable and disturbed men, usually violent, for whom an unstable sexual identity is part of that presentation - Barbie Kardashian being one of them. (I believe that BK is in fact imprisoned for violence rather than sexual crimes as such). I'm leaving aside the Karen Whites and Isla Brysons who look more like opportunistic advantage-seekers.
That really isn't the same as my friend's teenage daughter who socially transitioned to male in year 12 and has gone on to medical treatment, who is a long-nondiagnosed ND, and whose main interests are making textile art and reading.
But to say that it isn't the same is to challenge the narrative that 'being trans' is a biomedical or essential part of being human, rather than a highly cultural and psychosocial phenomenon that will wax and wane. So activists are stuck defending Tiffany Green as being exactly like Stephen Whittle to the point of referring to them both as 'trans folk' without even identifying their sex.