Just to expand, having a fixed sexuality that is unchangeable is an expression of “homonormativity”, which is to say it is queer identity that tries to coexist within the heteronormative default without challenging it.

It is easy to box oneself into a sexuality archetype like “gay” or “bi” or “ace” because they provide convenient labels that can be used to more easily understand/relate to others, and it helps to be able to organize and rally under a defined identity, but it fails to acknowledge that not everyone can perfectly fit the same mold, nor are they inherently going to follow the same path throughout life.

Semi-relevant side story: over Thanksgiving, I went to visit my folks, and walked in on them watching some cable TV channel which was airing an episode of Everybody Loves Raymond about (fittingly enough for my visit) a misunderstanding that Ray’s brother might be gay. And so there were some deeply uncomfortable canned laugh tracks at gay stereotype jokes that made my skin crawl before the two brothers confirmed their mutual heterosexuality, to great relief of both, but there was one line that stuck with me as having something of a grain of truth (paraphrasing): “Maybe I could be gay and I just haven’t met the right guy yet”.

Obviously if you’re a man who is into women 99% of the time but one day end up genuinely attracted to a guy, it doesnt make you “gay” (bi, maybe) but I’d argue that no one is inherently “gay”, nor can one be perfectly “straight”. Heteronormativity instills that concept of essentialism in order to perpetuate the “us vs them” binary of sexuality, and so essentialist identities are as much a trap as they are a convenience. People are better off thinking less “What am I” and more “Who am I attracted to”, and accepting that can change over time.