I do wonder if any of these people are at all monosexual. Or have actual relationships with actual people. Coz the argument they make against a female homosexual orientation that excludes males is that once you become romantically involved with someone, their genitals cannot be a dealbreaker unless you are a terrible transphobe.
I'm going TMI here just to illustrate a point, so please forgive me for the personal anecdotes to follow (and for how shallow I was in my youth).
I am attracted to men, fairly manly men at that. If I dated a bloke and then come sex time found out they did not in fact have a penis but a vagina instead, I would indeed be completely turned off. Utterly and completely.
In the case of a lesbian dating a transwoman with a functioning penis this would be even harder to imagine. They'd be extremely unlikely to pass as female having gone through puberty etc. But as transmen tend to pass better, let's assume I hadn't a clue before sex time.
I know finding female genitalia or a replica of male genitalia where I expect to find fully functioning male ones would turn me off because a) dishonesty is a complete turn off to me and I would expect to be told in advance and b) much smaller things have completely killed any attraction I've felt for guys before.
Such as the time that after dancing around each other for weeks and fancying the guy like crazy and dreaming of nothing but going out with him, when he finally, finally leant in for the kiss, his nose kept getting bigger and bigger and bigger and I literally run off after saying sorry I can't. Never told him why, it was too stupid after all, but I was completely cured. Not a shred of attraction left.
But fair enough, that was before going out with the guy so how about this relationship: Been going out with this one for quite a few weeks. Lovely dude, romantic, attractive, attentive. Went swimming one sunny day, diving in the lake, canoodling. Until I see a bogie had caught in his moustache. It was like a switch had been flipped in my brain. That was the end of that relationship.
Or one of my great loves, dumped me and broke my heart, then wanted to get back together after we wrote to each other for years (actual letters, sigh, how I miss that). Anyway, we met. And I was so excited, so in love, already planning the night... No idea what happened to me, to him, but it was without a doubt the second most boring date I've ever been on. I couldn't get away fast enough. He was completely confused of course and I couldn't exactly say what had killed off the spark. But dead it was.
So for these weird people to think that something as major as the wrong genitals couldn't possibly turn you off if you were romantically involved, it makes no sense to me given the nose, the bogie and the mindnumbing boredom that killed it off for me.