Right. Especially with self-ID, there seems to be little agreement on how to define transgender folx by others (meaning external criteria). And I see some contradictions among Trans-activists on who is included.
There may be some contradictions around the edges, but the basic premise by which gender dysphoria and transgender identity is defined is pretty clear (and DSM had no trouble in codifying it satisfactorily).
In lay terms, it's someone who does not identify as the gender ascribed to them at birth (almost always, of course, assigned on the basis of biological sex). And yes, a good proportion of the diagnostic climate is based on environmental social and cultural factors - in other words, how the person's environment attaches certain expectations, behaviours and attitudes to the gender spectrum (ranging from alpha-man to man to beta-man to neutral, through to the same spectrum on the woman side).
I don't think it's 'evil', but I suggest males will do a lot to satisfy sexual (hetero or other) desires. I volunteer on an anonymous suicide prevention hotline - I find others are surprised when I tell them about the high frequency of male masturbating callers
Sadly, that wouldn't surprise me at all (and in fact it's a narrative theme in an episode of "Inside No 9").
But those masturbating males weren't "pretending" to be women in order to go about their business, were they? And it's ludicrously easy to preserve one's anonymity (and thus undetectability) across the distance of a phone call. Those two factors, in my opinion, mean that there are few or no points of comparison between those masturbating male callers and a cisman pretending to be a transwoman in order to enter woman-only facilities/spaces.
I linked here a couple of days ago to a short twitter thread written by a woman (female) who works at a women's refuge. Her experience was that those transwomen who used the services had always been genuine as opposed to nefarious imposters, and that none of the ciswomen using the shelter (nor any of the staff) had ever experienced anything akin to an improper abuse in terms of phoney self-identification etc.
And I'd certainly love to see more empirical or anecdotal evidence around exactly what problems might or might not ever have occurred along these lines in places like public baths changing rooms and women's refuges. After all, transgender identity and gender reassignment surgery have both been recognised/performed for decades now. Surely if hetero cis men had been attempting to use the Trojan Horse tactic of a bogus self-identification as a transwoman in order to do horrible things to (or in the presence of) ciswomen in those sorts of spaces, the media would have picked up on it many times by now. Wouldn't they?