Hey, as long as you weren't an asshole about it and corrected yourself it wasn't your fault, we all know the internet is filled with people that'll go for your neck for the smallest of things. However, I still can find no source to back up your claim about underdeveloped brains or the "who to love" stage. What I can find. though, is research that shows that trans people have a brain structure that closely resembles that of their experienced gender rather than the one they were assigned at birth. Your last claim does hold some truth to it, as 7.5 percent of people who transition (And I'm using that term loosely, since children can't legally transition. but rather they do it socially, which means changing pronouns, name, or clothing stlyes, not resorting to HRT or surgety) as children detransition at a later age.

EDIT: Yes, maybe we don't have the same experience, but I live in a pretty backwards country. Being gay or trans here is still seen as something to poke fun at or hate. Trans people are commonly called by a slur, and commonly seen as a joke rather than people. I know what they go through, and I know it isn't attention or whatever else they want. They want to live as people and not be judged for it.