My peak was from way before the gender delusion became mainstream movement, because I wasn't a stupidly bias female who took the brain scans as conclusive evidence that there's "female" or "male" brain structure. Research as far as I know hasn't considered what causes the brain to develop structures that's stereotypically seen in humans and have not tracked the development of the brain structures stereotypically seen in female and male humans from day of birth to adulthood (and I came up with this thought without actually studying university level biology, watching YouTube nor discussing about this on reddit, in my early 20s) and I also knew since I was a late teen how bullcrap this whole "born in the wrong body" mentality (I never paid attention to this stupidity and lunacy until I began using Tumblr around that age).

I was raised in a family where I have to do a lot of self-reflection, value objectivity over subjectivity and being a lonely independent kid makes for a lot of personal conversations with myself (private thinking time which comes as a form of me talking to myself in my mind and feeling like I am actually talking to someone, which is a nice feeling to have and allowed me to accept my solitude throughout my life) and the ability to do basic research helps.

It would be nice to call it common sense, but considering how many people don't understand basic biology (and even neuroscientists seem to fail at maintaining non-bias in their research as you can tell by the language they used in their notes) people in general tend to heavily weigh feelings over facts, it doesn't seem so. Even I wasn't so sure at the start, hence why I spent so much time contemplating about my current knowledge and beliefs on how gender identity should apply to society and how it's already being applied to society (e.g. "female" is a term for the sex who reproduces in all animals, "girl" and "woman" are terms for female humans at different stages of their life).

Edit: Fixed some wording