most monosexuals think like this because of bi erasure and the idea of a gay-straight dichotomy. it's like if you're from a culture where "purple" was never really a color, and then when it catches on people start thinking of it more as "red-blue" than a color in its own right. also, a little more complicated than that:
think of a bilingual person who speaks both spanish and english. are they somewhere "in the middle" between spanish monolingualism and english monolingualism? no, that would be like, spanglish. bilinguals know both, leading to their own unique experiences/challenges/ways of thinking
edit: also, despite the prefix, bisexuality isn't restricted to 2 genders
Bisexuality is not 29 years old. This is a 29 year old article reporting on something created 30 years ago with Blur’s hit single “Boys and Girls”.
Used to be you could have girls who want boys, who like boys to be girls, who do boys like they're girls, who do girls like they're boys, but not anymore due to woke.
The birth of Quantum Homo State Theory: until observed with a partner, the Bisexual could be either Straight or Gay. Upon observation, they become one or the other. This state may or may not invert itself should the subject acquire a new partner.