I was thinking through each statement--as I am wont to do--and saw this one and thought, "Of course!"

And then, "Hey, wait."

I completely accept that some people have gender dysphoria, and that this causes there to be trans people.

But as you phrase it, this is the only source. Is that actually true? Does the set of trans people consist exclusively of people with gender dysphoria?

People can become tremendously fascinated by ideas and movements. They tie themselves to trees, blow themselves up, and engage in all other manner of extraordinary and potentially life-altering behavior because of their affinity with an idea or movement, completely without regard to gender or sex. People can take very dramatic action without a corresponding "dysphoria" (at least not one that is widely recognized).

It's difficult to envision people with gender euphoria wanting to change their gender and sex.

But what about people with gender aphoria? Is that a real phenomenon? Among those people, might not some, despite all the downsides, be sufficiently enamored of the idea that they would identify as trans?

More precisely, do we even know what the distribution of gender satisfaction looks like? Do we have an adequate way to measure, and do we understand how social pressures shape this distribution?

If true, this wouldn't impact how we ought to consider people with gender dysphoria. But it might make the issues more complex as a whole, if the number of non-gender-dysphoric trans people is not a vanishingly small fraction (or might not remain so). It also might not make things particularly different. But the existence of gender dysphoria is such an important phenomenon that it is used in critical parts of very many arguments; and if that premise were not always true, perhaps a lot would have to be rethought in the case of non-gender-dysphoric-trans people.