I've seen that before, that BDD is about how distressed you are about a physical feature, not about whether or not the feature makes you ugly, and some therapists probably treat it that way, but I'm not sure that it's technically true. From the DSM 5:
A. Preoccupation with one or more perceived defects or flaws in physical appearance that are not observable or appear slight to others.
What counts as "slight" is obviously subjective, but I think it hinges on whether or not the preoccupation is reasonable or delusional, because a reasonable preoccupation (a person who has suffered facial disfigurement, for example) doesn't respond to medication but an unreasonable preoccupation does. (Don't quote me on that, but I recall reading that somewhere.) So the diagnosis can impact treatment decisions.
If the preoccupation is unreasonable, then medication can help because the evidence that the person is basing their preoccupation on is self-derived (it's not coming from other people, who pay no attention to the "defect" at all, but from the OCD fixation). If the preoccupation is reasonable, then medication doesn't seem to help because the evidence is based on real feedback from other people (ie. the person is actually being ostracized). If you are legitimately "ugly" then they usually treat for depression and anxiety instead of BDD/OCD; the coping strategies are different. (I'm very far from being an expert, though.)
This was really good, btw:
it's a bias where you process things visually in a piecemeal fashion rather than gestalt, which leads to getting fixated on features and difficulty seeing how everything can sort of work together even if an individual feature looks odd in isolation
I've never thought of it like that but it's very illuminating. I have a lot of physical flaws, and I can
identify them individually, but I don't obsess about any one of them, even in serial fashion. I'm ugly in an overall, gestalt kind of way. (Which is almost even more interesting because I do have OCD. But my OCD is about other things.) There's no limit on the number of perceived flaws so far as a BDD diagnosis goes, but I think it still hinges on whether or not the distress is reasonable or not. A person with BDD can have 20 distinct fixations and every one of them can be so insignificant that no one else would notice any of them. It gets really murky though trying to determine whether or not a person's distress is reasonable. I guess in borderline cases they just prescribe medication and see if it helps.
In my case, I think not passing creates reasonable distress. If I were cisgender and I felt this strongly about my appearance, that would probably be unreasonable. The jury's still out, though, and my OCD may be playing some role. I've talked to my therapist a lot about my appearance issues and she's never raised the prospect of BDD, so I get the impression that she considers my fears at least somewhat reasonable. I think it all just gets filed under sequelae of gender dysphoria.
I don't think my YT videos will be very good, tbh, haha. I don't think I have the right traits to be a "personality". I mostly just feel pressure to get my ideas out there. But thanks.