You mean dysphoria. Dysmorphia
is a medical term, but not one that applies here.
And let's be truthful with each other for a moment. Transgenderism or gender dismorphia IS a mental condition. There is nothing wrong with the body, the desire to be the other gender as to what the body developed into (you aren't assigned a gender, medically they assign sex and sex and gender is an interchangeable term in the medical field) is strictly contained within the mind.
Not quite:
physical biologists may refer to sex and gender in interchangeable ways, though they've been moving away from doing so recently. But the "medical field" includes psychiatry, developmental paediatrics, counselling & mental health, and in those fields sex and gender are
not used interchangeably.
Dysphoria describes the mis-match between physicality/morphology and gender identity. Researchers & doctors uniformly agree that the latter is
not simply an expression of the former, so it's not sufficient to solely address the latter purely via therapy.
If we're talking about actual measurable success rate, GRS (alongside counselling) is generally successful. Much more successful than solely therapy. It does not make sense to try to improve quality of life by shifting away from the approach that has brought us by far the most success so far with improving quality of life.
Maybe that's just a fundamentally flawed way of going about doing it, kind of like treating an alcoholic with alcohol.
I mean, the individual usually isn't just flat-out asked, and their answer taken unquestioned. The individual is usually asked by a professional, who can ask further questions, probe a bit, analyse, and determine from their own expertise whether the improvement is authentic and genuine.