I spent at least 56% of my essay discussing the science behind my beliefs. As you admit in your own article, there isn't that much transgender brain research yet. If you read the Psychiatry Advisor article I cited in my essay, some similarity was found in the hypothalamus between some cisgender women and some trans women, but Dr. Joel said "the finding that these measures do not add up consistently in all cisgender men, cisgender women, and transgender women runs against the hypothesis that there are male and female brains, and that transgender individuals have the brain of the other sex."
Given that your brain changes all the time, such as when you pick up a hobby or start a new job, and that it probably changed during the pandemic if you modified your routine, of course it would change if you switch genders.
Science isn't as objective as people think it is. Before any data can be collected, someone has to formulate a hypothesis (guess) as to what data to look at in the first place. There are poorly designed studies, errors in data collection, faulty interpretations of data, poorly communicated findings, inaccurate reporting, and then the public plays telephone once they read the articles. Neuroscientists, as in any other profession, come in a range of ability and integrity levels, each with their own unconscious biases.
As I summarized in my essay, Gina Rippon discussed the problems with the studies that supposedly found sex or gender differences in the brain, the few differences (out of hundreds of areas) are very small, and often are easily eliminated by a change in behavior, keeping in mind most parents steer boys and girls down different paths pretty much upon birth.
We haven't reached the end of all knowledge--there's still much to be learned. The question is, what is the least harmful path given what we know today? If boys, on average, have a small advantage over girls in one area, but girls can easily make up that difference with a little extra training, and studies show they do worse on tests when reminded of that difference but perform better when they're primed with a more positive message, and many girls do better than boys anyway, is it the best policy to hype up that tiny difference? The current gendered world is much more harmful than a nonbinary one. Our time is better spent trying to give everyone equal opportunities and respect, and warning parents that even babies are keen observers of gender rules, rather than arguing about these tiny differences.