It appears that the best current scientific thinking is leaning heavily toward gender being innate and predominantly genetically determined.

For instance:

Polderman TJ, Kreukels BP, Irwig MS, Beach L, Chan YM, Derks EM, et al. (March 2018). "The Biological Contributions to Gender Identity and Gender Diversity: Bringing Data to the Table". Behavior Genetics. 48 (2): 95–108. doi:10.1007/s10519-018-9889-z. hdl:1871.1/acbbef10-1339-495d-8cc6-0d3f02742596. PMID 29460079.

https://www.sciencedirect.com/topics/social-sciences/gender-identity

This is the so-called "essentialist" view, and is the only one grounded in any kind of objective fact. The "social constructivist" and "performatist" views are the result of work in psychology and social sciences. Given that the replication crisis is overwhelmingly centred on those sciences, there is reason to be skeptical of that work.

Overall, then, the "best" information there is these days, is that gender identity is innate.

If that changes in the future, then we'll have to revise things, and perhaps you'll have a chance to vindicate your views then.

But only then.