Bisexuality is often sexualized. It's often seen as a call for attention, and performative. That fication of sexuality actually puts a lot of bi sexual people at physical risk from things like sexual assault. The resources that you have after something horrible happening to you are often deeply inadequate. Those kinds of misconceptions are omnipresent. And so as long as they exist, it pushes people into the closet - both heterosexual communities and queer communities.