StrangeAdventure I know you have gone to bed, (as I should too) but I just wanted to add that you seem to have an idea of what trans means that is not necessarily related to what is happening now.
"And once she has had HRT and GRS, and various other treatments, she will have has acquired some of the physical traits of a cis-woman, and lost some of the physical traits of a cis-man. In particular, she loses the muscle mass, aggression, libido, and penis that make some cis-men a potential threat to women. If it makes her feel better, and allows her to enjoy life, hold down a job, and contribute to society... why not? Sounds like a win-win solution to me."
Well that would all be great for transsexuals of course, and I know a transsexual who transitioned early, although not as a child of course, and is very happy being a transsexual woman.
However, many transgender women now will not have surgery or necessarily take hormones. They will not lose muscle mass. They may have surgery to create female-looking breasts, but may still retain their penis. And hormones may not affect their ability to use their penis.
You may wonder why this matters, well, as far as I see it is confusing. My transexual woman friend is angry that transexual people like herself, who have identified as female for a long time, not benefitted from male privilage and are no threat to women (and just want to live their lives quietly) have been used as examples for others who have lived as men for a long time, benefited from male privilege and are now identifying as women.
My friend had no opportunity to identify as a man, she was way too effeminate to 'pass' as a man, was sexually attracted to men and wanted to live as woman. Her life does indeed follow the pattern you state, but this is not now the norm of trans gender.
Anyway, to no one in particular, many women are now very concerned about the proposed self identification bill which, if it comes into law, could see any man identifying as a woman. The issues are much more complicated than the Horizon programme presented.
It's also important to note in the horizon progamme there were only two trans men and one trans boy, and they were all very young, compared to twice as many trans women of a variety of ages. Trans men and trans women do not all seem to present with the same issues and concerns, it just does not seem to be very similar in the way 'trans' can affect males and females. Who is doing research on that I wonder, that is not to anyone in particular!
This issue will not be going away and it is important that reporting on it gives more facts and not just emotive appeals. The Horizon programme gave a very one sided view.