“Straight” isn’t a sexual orientation, it’s a position of power.
What I mean by this is that “Straight,” as the privileged class in a system of oppression, has the power to construct itself with arbitrary rules that go beyond “who you’re dating.” Straight people decide who and how and what is Straight, and Straight people enforce that canon to keep themselves in power.
Acting like all “sexual orientations” have equivalent meanings (”gay people are attracted to the same gender, straight people are attracted to the ~opposite~ gender”) ignores a lot of the fundamental ways that Straightness maintains and wields its power, and absolves Straight people of their complicity in the oppression of queer people.
Straightness is a monolith. Straight people have made it that way. A person can’t access Straight privilege simply by being in an m/f relationship or engaging in m/f sex; a person can only access Straight privilege by being Straight, and it’s Straight people who decide what that means.
And this is why ~bisexuals in “straight” relationships~ is Bad Discourse, and this is why het+asexuals and het+aromantics can never be Straight (and why that does not invalidate lgb+ace/aro identities), and is why your respectability politics and “We’re just like straight people, except we’re gay” rhetoric is dishonest garbage.