You've made a lot of strong, specific assertions here that contradict my own understanding. For example, you seem to be dismissing some troubling questions regarding sex assignment at birth based on on-the-spot judgment calls. It's probably a good idea for you to provide links to some objective sources.
The fact that you're confused about this most basic biological fact is exactly what I've been trying to communicate is the problem with gender activists in this space. They've spread considerable misinformation on this topic.
"Sex assigned at birth" is one example of the kind of misinformation I'm talking about. They're equivocating on the term "sex", because doctors are not determining biological sex, but making a determination of legal sex. If they had argued for "gender assigned at birth" for legal purposes, and argued that both sex and gender be determined and recorded (because sex is important medically), there would be no such confusion.
Legality is what we're talking about, though. The government decided, against all reason, that this was something they needed to get involved with. So that means what whatever your definitions of sex and gender are, or whatever definitions the Wikipedia editors are accepting this week, they should not be used to discriminate against any individual, no matter how uncommon their physical traits and sense of identity may be.
I don't know why you think we're talking about legality when this whole thread was about biology. The legal status of one's sex is supposed to follow from biology, but the point is that this is an imperfect process at this time.
As for the legal issues, nobody supports "discrimination" in an abstract sense, but the point is that there's a strong difference of opinion on what counts as "discrimination". If "sense of identity" is all that's needed to trigger some discrimination clause, a quality that cannot be verified physically in any way at this time, then that's a recipe for abuse by bad actors.
