Earlier quoted context omitted.
Wouldn't the Reimer story support a naive version of biological sex moreso than an acceptance of gender identity?
It supports believing people about what their gender identity is instead of imposing it on them. The rate of attempted suicide in transgender people is over 40% if they are not socially supported. That rate drops to general population levels in trans people who have familial and community support when transitioning.
Long-term the evidence is the opposite. Claiming that the difference between long and short-term outcomes is explained by the difference between support levels is not science. It is guessing.
"One hypothesis, the social stress model—which posits that stigma, prejudice, and discrimination are the primary causes of higher rates of poor mental health outcomes for these subpopulations—is frequently cited as a way to explain this disparity. While non-heterosexual and transgender individu- als are often subject to social stressors and discrimination, science has not shown that these factors alone account for the entirety, or even a major- ity, of the health disparity between non-heterosexual and transgender subpopulations and the general population. There is a need for extensive research in this area to test the social stress hypothesis and other poten- tial explanations for the health disparities, and to help identify ways of addressing the health concerns present in these subpopulations." https://www.thenewatlantis.com/docLib/20160819_TNA50Sexualit...