@DadJoke
It's not novel, it's baked into the EA2010 in the form of gender reassignment. Conflicting rights are common. and the law handles them. These are legislated rights. Not the strawman of "being treated as what you identify with" in general. There are no rights associated with "identifying" as anything else.
Firstly, the EA2010 isn't an old piece of legislation is it? It's a pretty new piece of law yes?
Secondly, this started out as about transsexuals and medical transition, with the ECHR case. In very recent times, this has morphed into a demand for "self ID" and "trans women are women", and, "it's not a mental health condition", "trans rights are human rights".
So yes, we are talking about a radical new basis on which to claim "rights". Doesn't matter if it's in a recent piece of legislation to whatever degree. That doesn't stop it being "radical" or "new" as a principle.
As for "conflicting rights", it's for the advocates of controversial rights claims to support them yes? You can't just appeal to it being in the law. So what? On what grounds should it be in the law in the first place? You can't say, "trans rights are human rights", unless there is some underlying good justification for the principle.
It's a strawman to bring up identifying as other things? And why is that?
You can show that identifying as one type of thing makes good sense, but self identifying your racial identity is clearly way different?