Asklemmy

This is just from the top of my head, but I suppose that it goes back to first principles: gender essentialism is a key ideology organizing society and extending to sexism, homophobia, genderism and transphobia. Then gender essentialism dictates broad sets of behaviors that are based on cisgender and heterosexual expectations, including sex temperament.

It may not come up often, but as long as it is visible as a distinct "thing" then it can get you in trouble. A cis-passing trans person might not get everyday harassment etc, but that does not mean there is no murderous transphobia. Similarly, a demisexual cis man can get in trouble because not being enthusiastic about women can have him pegged as gay etc, so he has to pretend he is consumed by sex drive to fit it. Then there is all the social BS asexual people get which includes negative stereotypes (like being repressed latent homosexuals and/or SA survivors) and overall diminishing their voice, like "it must be ...anything else" except for you not genuinely want sex or being attracted to people of any gender.

There might not be pogroms against asexual people, but that doesn't mean there is not invisibility and discrimination once you scratch the surface. It can go as far as life and family benefits that are structured around the expectation that people get sexually and romantically involved, form core families, bring up kids. Not only parents and relatives might get nosy if you are not dating or have a family by a certain age, but there might be salary and welfare adjustments that also make these assumptions.

Being asexual is connected to the main oppressions queer and trans people face and there is no reason to take asexual oppression less seriously than sexism, homophobia, and transphobia, because it is interacting with those.