I consider your theorizing of "pre-transition history" being within the "rights of society" to "keep in touch with reality" as misleading and problematic.

In fact, these are the axioms of trans erasure I discuss in my other response. In the core of this reasoning is the idea that "men are inherently dangerous to women" therefore "women must know at all times the biological sex of any person they interact with".

So you can't go past the "transition" history for reasons that under all other circumstances you would decry as "misandry", but only apply this to trans women (victims themselves of cis violence in bathrooms and all other settings). Why? Because you register trans women in the semantics of sexual perversion. Then, the "right" to know anyone's medical history does not exist, on the contrary people have the right to privacy to medical interventions of any type.

Due to stigma and discrimination trans people are furthermore entitled to hands down secrecy, given that a random bigot can just shoot them down for being trans with zero consequences. But this is also hypothetical now. The amount of cis-passing is different for every trans people.

Some may pass for cis, most don't. Besides the existential crisis some people experience when they can't tell a person is trans, in practice stealth trans people are relatively rare, and there is not an iota of evidence that there is any societal harm from stealth cis-passing trans people. So there is no reason behind your purported "societal right to know", apart from cisgenderist entitlement.

Enforcing such right is not only infeasible, but it sufficiently and necessarily leads to banning public trans life, with no other explanation other than cis people's uneasiness. The civil rights movement has established that majoritarian uneasiness with minorities sharing their bathrooms is not enough to justify perpetuation of discriminatory segregation practices.

This is textbook transphobia.