This guidance from the US Endocrine Society on transgender treatment has been discussed before, but an element of it was not discussed (I think).
https://academic.oup.com/jcem/article/102/11/3869/4157558
In the guidance, there is this little nugget
"Biological sex, biological male or female: These terms refer to physical aspects of maleness and femaleness. As these may not be in line with each other (e.g., a person with XY chromosomes may have female-appearing genitalia), the terms biological sex and biological male or female are imprecise and should be avoided. "
How can this make any sense? Female XY cases are very rare, yet in most cases, if I were to visit an endocrinologist and say "my little girl has started growing a beard and I'm concerned", would an endocrinologist really find it imprecise to say "actually your child is biologically male as he has testes and he has started puberty"?
Furthermore, isn't the whole concept of transgender not possible without the concept of biological sex?