And to further play the devils advocate there were plenty of people at the time that believed gay people were a blight on society for multiple reasons. Hence why conversion camps were a thing.
Like if you were born in a society where religious zealots who espoused bisexual bigotry just didnt exist, toxic masculinity wasnt a thing and there was a bunch of bisexual representation in media would you have had that anguish? very unlikely.
People with gender dysphoria face the same negative external influences as you do, arguably worse (lets be real, much much worse) but if it would be removed and they lived in a world without it they would still be discontent with their state, to the point of depression which would result in a poor quality of life and for many suicide.
Thats the hallmark of the disorder. thats what gender dysphoria is.
Lets do another thought experiment, what if we lived in a society where gender reassignment surgery was impossible. like lets ssay we just didnt have the advancements in surgical techniques necessary, but we had much better pharamcuticals. If surgery was impossible, but giving someone a pill like I described in the first thiufht experiment was possible that would be the morally correct thing to do as opposed to doing nothing, right?
Lobotomies were used as a cure for all kinds of different things. If you knew something was a problem and lobotomy was the only thing that seemed to cure it, is it morally correct to do so as opposed to doing nothing? That's why these simplistic thought experiments are bad because there are examples of what happens when you take it to their logical (and often sadly real) conclusion.
Now you understand the reticence towards gender reassignment surgery and why someone would be looking for much lower risk pharmaceutical treatments for gender dysphoria, which is exactly what we ended up doing with brain disorders?
It's worth noting that we still do brain surgery on people, and that we're even moving towards using implants to modulate how the brain functions, as opposed to the crude technique of severing parts their brain with rods jammed into their noses or holes drilled into their heads.
I have a feeling that we'll look back on this time when we cut off penises and inverted them into crude vagina like canals, jammed silicon bags full of salt water into chests and pumped people full of hormones as barbaric as the lobotomy era.
They're things that we do out of convenience because they're the best that we have, not because it's what we want to do.
I'm pretty sure this is 100% false. If in doubt, ask your local Catholic priest about it.
People with BIID and Gender dysphoria will kill themselves if they don't receive treatment, and will otherwise ha e poor life outcomes due to the adjacent side effects like depression and self harm that comes.
The only negatives that being bisexual and homosexual have come from external sources as you state.
In other words bisexual and homsexuao people are in a state of homeostasis while people with BIID and Gender dysphoria are not.