Brains tend to vary wildly in terms of structure, but for us they tend to function more towards our desired gender and that involves relying on hormones, especially once puberty starts. There are problems before puberty, but they don't become especially severe for those who get dysphoria until puberty.
Of course, brains vary wildly: There could be trans people who don't ever go on HRT but socially transition and there could be trans people who don't experience dysphoria but instead experience euphoria. As well as trans people whose Gender Dysphoria isn't so severe and, as a result, goes untreated for decades.
Mm this is a very good post, thank you for your insight. One thing I’m actually really glad you brought up is how diverse the human brain is. People are really stuck on trying to fit the entire human experience into a black and white category. The truth is we actually just don’t even know. Our brains develop in infinitely nuanced ways, completely separate from every human being on earth. Even identical twins develop differently, however small or large, because they simply can’t experience the EXACT same thing. NO one can. The stimuli from your environment and the coding in your genes creates distinctly unique consciences. Yes, there are PLENTY of parallels and similarities between brains that are MEASUREABLE and scientifically fact. However the brain is so loving complex, that claiming to understand and create authority on the matter is just stupidity or ignorance, or both. I liken it to describing colors; a lot of people can agree a color is “red”, but how do you know what you see is exactly what someone else does? You couldn’t, not unless you were them. There is so much we DONT KNOW about the human brain, and the human experience. Things that aren’t measurable, yet. The greatest tool we have is sharing your experience, even if words can’t describe how you feel.