I admit this has been less than a handful of times (can't be more than 3 or 4) and all in the past (the most recent probably 3-4 years ago) where I've seen people go "I'm heteroflexibe hurr hurr" in a jokey-way because they just DO NOT want to call themselves "Bisexual" because to them bisexual has too much baggage (and also I feel like they just didn't feel bisexual enough to fully commit to the "bisexual" label) back then there was a whole thing about celebrities like Raven Symone calling themselves Queer/Pansexual/"I don't want to label myself" basically ANYTHING BUT "bisexual" despite fitting that definition, and it really started making bisexual people feel insulted. But you say hetero/homoflexible people see themselves as under the bi-umbrella nowadays, that makes me happy. For such a long time these types of people made the rest of us feel like they think "bisexual" is a dirty word, they're actively trying to distance themselves from it.