I think if it was primarily genetic, there wouldn't be this massive increase in transgenderism in recent years. There may well be a genetic component to the genuine dysphoria cases, but if it is true in all trans people, why would some de-transition?
I was confining myself to gender dysphoria in order to address the original question directed at me which was would trans children exist if there were no gender stereotypes? In other words, there is strong evidence that gender dysphoric (trans) children would exist regardless of whether there were gender stereotypes or not.
As to the more general case where there is no dysphoria, there are a number of possible explanations, and I don't know which are correct. For example, the acceptance and visiblity of transgender people has increased, so transgender people are more likely to "come out" as transgender, some people are being mis-diagnosed, or there there is some kind of social contagion.
What do you mean by a 'similar, physical, root cause'? Are you suggesting that their bodies are actually defective?
I meant the gender dysphoria has a physical, genetic cause, that's all. Whether you thing they are "defective" or not depends on whether you are a GC feminist or not.
Gender dysphoric people who are born female and have grown to adulthood are women. I don't think anyone here would say otherwise. What makes you think that most medical professionals disagree with gender critical people?
Now we are back to square one. As a GC feminist, you consider women to be "adult human female" and you don't think there is such a thing as gender incongruence; others disagree. That's what this whole debate is about. You think women = sex; the others think woman = gender.