I don't know how anyone could look at the swath of laws introduced throughout 2020-2021 in both the US and in the UK and actually believe that people are not trying to police trans identity.

> by loudly insisting that any kind of socially non-normative gender expression should be seen as tantamount to and ipso facto equated with some sort of trans identity.

I mean, no. One of the good side-effects of allowing people to be more comfortable with gender fluidity is reducing stereotypes about what men and women need to look like and how they need to act. It means less telling women that something is wrong with them if they inhabit traditional male roles or have certain body types.

This is helpful not only for trans people, but also for non-conforming cis people. The less that people are freaking out over somebody calling themselves a girl if they don't look a certain way, the better things are for everyone who is not inhabiting a traditional gender role, whether they be cis or trans.

> Need I point out how this policing may be harmful to non-heteronormatively-expressing folks?

No, you don't need to. As I pointed out above, this policing isn't happening, and breaking down social norms about gender expression creates safe spaces for non-heteronormatively expressing people, regardless of whether or not they identify as trans.

An advantage of separating concepts like gender, sex, and presentation is that non-conforming cis people can feel more comfortable saying, "my appearance/interests do not make me less of a woman/man."

The idea that trans people are telling girls who like sports that they have to be men just so fundamentally misunderstands what the trans community actually believes about sex and gender. Trans people largely believe the opposite of what you say, they are pushing back against the idea that you can be "prescribed" an innate gender-identity by society.

Also, why is it that you refer to people who advocate for the validity of the trans experience as "trans activists" but insist on using the term "gender critical" to describe those who advocate for the position that the trans experience is invalid? Would not a more appropriate term be "anti-trans activists"? Is the resemblance to the "pro-choice/pro-life" argument - i.e. using a euphemism to avoid saying what the position is descriptively and clearly - purposeful?

While some people with highly traditionalist views might indeed believe this, many gender critical folks do not. Trans identity can definitely be valid, but so can cis identity. And it's definitely wrong to conflate any and all non-normative gender expression or presentation with some kind of all-encompassing "trans experience", at least in the strict identity sense.