I don’t see any difference between male and female ability in regards to intelligence. Saying that their brain develops differently seems like an invitation to the argument, that women aren’t mentally able to do the stuff men do.

This is a pretty slippery-slope-ish argument. Brains have plenty of differences that don't have anything to do with general intelligence. There's a lot going on in there.

The brain differences are extremely minor and as far as I understand it, the brain differences aren't exclusive either.

This is a study I read a while back. I just skimmed it because I don't have time to reread it right now, but it looks at brains as a mosiac instead of being on a continuum.

https://www.sciencedirect.com/science/article/pii/S0149763420306540

I'm not super familiar with what specific aspects of the brain are different between men and women, but the fact remains that there are differences at least in the manner in which the brain processes certain input related to sex & gender, as well as the cortical homunculus (which I suspect is probably the area of greatest contrast and even that's pretty minimal).

Science has also looked at the question about difference in ability and found that there's no statistically difference in the brain's ability between men and women. So no, this isn't a dangerous question that's going to lead to a slippery slope of claiming that women are less able than men. That claim was already being made and has already been investigated and debunked.

I don’t see any difference between male and female ability in regards to intelligence. Saying that their brain develops differently seems like an invitation to the argument, that women aren’t mentally able to do the stuff men do.

Pretty much every group of people will have slight differences in pretty much every area, if you look closely enough. So it makes sense that the most divisive biological things we have as a species (like biological sex) are going to yield some differences.

No, transmedicalism is the belief that somebody isn't actually trans unless they meet certain medical criteria. I'm saying the opposite: that the lack of any particular medical criteria can't be used to invalidate somebody being trans.

As for your second question, how a person behaves is a matter of nurture more than nature, but it's also deeply engrained from a very early age. Even those trans people who put the effort in to overcoming this socialization can have old habits they struggle to get rid of.

Whenever there's a big line, I'll remind the people in line of this. We don't care. Internalized sexism keeps them stuck in line

I also met women who explained this to be because of fear for their safety, that they don't want to be around men in the toilet (or anywhere in private).

I find that maybe an overreaction, but I'm not a woman to be sure