Well that would include me in a way...
Women who like men but who have never had sex with a man are allowed to call themselves straight or are assumed to be heterosexual so why can't I as a woman who has never had sex with a woman call myself bisexual, you know?
I DON'T want to enforce a sexuality on anyone.
However - I do think that part of the anxiety and reluctance to call oneself bisexual comes from misrepresentation of what bisexuality even is. "Not gay enough to be bisexual" - an idea that bisexuality is a 50/50 split. When it's not. Why DO we have to put percentages on everything, you know?
I don't think bisexual even has to describe a gender binary. It's just a weird, messy strange territory between gay and straight and I think it needs to be widened and developed. I hate the 50/50 split idea.
But I do think there is so much stigma around bisexuality and that feeds into this idea of people NOT wanting to be associated with it. If you're bisexual - you're greedy, you can't choose, you're a slut - all sorts of nasty shit. And people internalise that. It's easier sometimes to pretend you're not bisexual. To not have to deal with those nasty preconceptions.