Also, the way you dismiss genderfluidity as not a genuine identity is serious overreach. There are few studies on nonbinary identities in general, so saying things about them like that isn’t scientific. It seems more based on your own experience of gender than anything else. For all you know, there is a constant fluidity to everyone’s gender, with some having more than others. Maybe you never dip into another gender, but how can you say others don’t?

It’s exactly why the brain sex arguments are often generally considered transmedicalist pseudoscience.

We also can’t say that gender truly does not change, only that we don’t know how it could change, and that all attempts to alter it carry near certain risk of serious harm. There aren’t many elements of our psychology or personality that can never change, as our brains are physical substrates that can change in countless ways.

Exactly, honestly the idea that it can’t doesn’t seem to add up, our brains are constantly changing. I wasn’t the same person 5 years ago, 10 years ago I was also completely different, and 15 years I was also different. If our personalities can shift and change throughout our lives who’s to say gender can’t either.

The fact that we’ve seen little evidence of gender changing with brain damage indicates that it is a more distributed phenomenon. This makes it similar to consciousness, which does not have clear correlates either.

Keep in mind that traumatic brain injuries which completely reshape a person’s brain and mind are much rarer than one would believe reading neuroscience papers. Most people who suffer critical brain injuries like a bullet to the brain, a knife through the head, or even a steel rod through their skull succumb to them. They never live to tell the tale. Those like Phineas Gage are the lucky ones, they don’t say they cheated death for nothing. It’s very possible that specific brain damage could cause a change or diminishment of gender identity, or gender feelings, but we’ve never seen someone with that injury, or they had more than just that injury and died.

Brain injuries can change large parts of a personality, they can completely change a person. I think it’s naive to say that it couldn’t alter one’s gender perception. Especially when we just don’t know, there’s so much about the brain we don’t know.