Why do FTMs always engage in the girliest shit imaginable while wanting everyone to see them as boys? The psychology of pooners is a genuine mystery to me. With AGPs it's super obvious what their deal is, but what is prompting young women to reject their womanhood while still indulging in femininity?
It's because you're not in the right mental state. Try not going outside in the sun for 2 years straight while only looking and interacting with anime and game lovers on tumblr, twitter, tiktok, etc..
I think it's a mix of wanting to feel pretty and engage in hobbies they had beforehand and coomerism/portrayal of ideal beauty. Being a "man" is just an identity, not what they are. Which is how most people act, but these guys treat it like they picked up emo or the piano, not like they were raised by birth to be men. Raised by birth men have cultural differences, fake men can just choose to stop being men at any time, and that's genderfluidity or destroying toxicity over men or something. It's more brave and stunning for a man to choose to engage in girly hobbies than it is for a girl.
The second one though... Do you know what a catboy is? You likely do. Do you know what the anime, non-keffals version looks like?
Even if you don't like the super androgynous kawaii look, you can go batshit crazy with other fangirls over resident evil pretty boy Leon Kennedy, a current flavor of the month:
Notice how the conflict of masc and fem traits come through. This is attractive to them (I personally like him normal and not cross dressing but that's me). This is what some anime transmen are trying to skinwalk. These are anime loving coomers into a kawaii anime type of deal. Male weebs fail at skinwalking anime girls, female weebs fail at skinwalking pretty anime boys.
Also, say you're into an expensive fashion hobby like Gothic Lolita (frilly dresses) or decora (a lot of crap on you like the troon woman we're talking about). That's a huuuuuuuge money sink: you have at least 3 outfits that cost 200$ each, you're going to throw that out when you spent that much money just because you have crippling body hatred? No! Everything will work around your likes and incorporate them.
TL;DR: being a man is part of the edginess of the fashion statement, they might be an anime skinwalker, they spent a ton of time and money on the hobby already, and they just like the look of male/female.
And yeah, some women are just that uptight and scared to express girly traits unless they have a hideaway or excuse like "I'm a male, therefore I am not vunerable or my mother." Yes, that's hard to understand to outsiders, but that's because mental illness tends not to make sense if you're not in the position. They probably have a bunch of hangups to unravel that we didn't experience combined with a way their brain works, maybe a black and white view that is common to things like anxiety, autism, borderline, etc. that we go "what the fuck are you talking about?" at, but they can't help but indulge because their brain is rooted in that and they won't stop it until they choose to get help (and knock the trans shit off).