Earlier quoted context omitted.
These are good points and great questions! Your description of getting surgeries based on a distorted view of what they see in the mirror sounds exactly like gender dysphoria to me. I have a big nose like you and even having had romantic partners compliment me on it hasn't stopped me feeling bad about it, but I agree it's definitely more trivial than believing you ought to be the other sex, somehow. They usually say…
It sounds like we have established that body dysmorphia and gender dysphoria are not really the same thing? Two conditions can have a similar thread but not be the same or even related, nor require the same approach or treatment. In terms of "people being convinced by others", I think this is a relatively recent phenomenon. I think it's possible to be simultaneously concerned about social contagion and social influen…
Just my alternative conclusion is: you can't fix anything by compelling people to play along with someone else's delusion, whether the source is social, psychological, biochemical, sexual, whatever.