Biological sex is not a binary
Yes it is. This is the factual science bit. As with many things in science, we learn more about it all the time, which is why "intersex" is an outdated term. Thanks to better scientific understanding, we now know that every DSD is sex-specific. Many will be spotted visually (as looking unusual) at birth and then verified by testing. One that is likely to keep being missed at birth is 5-ARD, because the genitals don't grow as they should have done until puberty. Exterior genitals are the last part of the body to grow in the reproductive system, so until puberty any boy with this DSD will have "default" looking genitals because the growth process was interrupted. In other words, they'll look like a girl.
This is a sensitively written article which focuses on this DSD:
https://www.bbc.co.uk/news/magazine-34290981
Unfortunately, until the public fully understands that this DSD only affects boys and that they have a standard male puberty, we'll probably keep seeing more boxers and 800m runners with it successfully entering the women's events.
Gender is a social construct. We made it up! We can do whatever we want. We chart all our own paths.
Agreed. Obviously ideally children and vulnerable young people don't get confused about the difference between the social construct of gender (identity) and the biological reality of sex when trying to figure themselves out. Pushing against cultural expectations and limitations is difficult enough without having to think about body modification as well.
I caution trans kids that they can't control how others perceive them and that their identity is internal and not determined by how other's see them or address them
This sounds like good advice for gender questioning children. Hopefully they will listen to this and feel less distressed if people don't use their preferred pronouns. Identity in this sense is an understanding of who you are in amongst the rest of the world e.g. how you fit. Everyone goes through a journey on this throughout their lives, but most intensively during puberty.
I think gender criticals should remember they can't control how others perceive themselves.
Well, yes. I've been misunderstood on this thread, despite my best efforts to explain what I meant. But then the same advice applies to everyone.