>rather than the more typical trans narrative of always knowing who you were "deep down".
That's more of a stereotypical (though still pretty common) narrative than a typical one. What is typical is feeling a form of unease or discomfort over being your birth sex, even if you don't identify it or the cause of it for a while. You can still very badly want to be female, or at least feel depressed and uncomfortable by not being female without consciously knowing why, without identifying as a girl/woman. For a lot of people it's more a matter of semantics or interpretation of gender theory as to whether they consider themselves to be "women on the inside" without physically being that way.
I mean, she is clearly trans with a fetish for sissification/feminisation. If you read her Tumblr you have posts about her dysphoria and how she just wants to be accepted a a normal girl and her support of trans right juxtaposed to posts about her being a feminised sissy slut or how much she loves trapping straight men. She's explicitly said the reason she does porn and does it exclusively as a bottom is to show that trans women can be women too, and don't have to be defined by their genitals.
To me it looks like she considers being a feminised male who's gone so far as to become a woman such that she's treated like a woman and is sexually desirable to men as a woman regardless as validating to her womanhood. As an MtF who also shares similar fetishes I can identify with how she feels a lot. Not being totally female and having to approximate it by feminising yourself is a bad thing, but by framing it in the context that it doesn't matter because you're a woman anyway, and making it actually a good thing, it becomes something to be enjoyed rather than something which makes you uncomfortable.
The clip in the OP is really satisfying to both the fetish and the dysphoria. Things like "the first time I heard an audio clip that said I was just a girl and I couldn't be anything else"; it's "forcing" you to be feminine and you can pretend it's something you're made to believe, but really it's just expanding on things you already feel and validating you.