You should be careful with mixing in biology with new-age gender ideology. The majority of gender ideology is not founded upon objective science.
For example, we do not know why a human being would be born with a sexual orientation that is counter-intuitive to maintaining the human race (being gay), biology does not explain that. In the same way, biology can not explain why someone would believe that they are the opposite sex. That is what the mental health field is for and none of the sexuality-related mental health disorders have a biological and objective basis. Being gay was removed from the sexuality-disorders because of this but they really should have removed all of them if they weren't playing politics at the time.
Bit of a rant. Just don't like seeing people make arguments that seem to imply this stuff has objective proof to it. We understand that some people are different, and we should accept that within reason. That does not mean how they think is supported by science. This is why people will often troll and say "well, I think I'm another race", or "I think I'm a cat". They are stress-testing the science of gender ideology and it falls flat because there is very little of it.