There is nothing biphobic about mspec identities that aren’t bisexual.
People identifying as pansexual isn’t biphobic.
People identifying as omnisexual isn’t biphobic.
People identifying as polysexual isn’t biphobic.
People identifying as any other mspec identity that isn’t bisexual is not biphobic.
Someone finding an identity other than bi a better fit is in no way biphobic. Acting like everyone who is attracted to multiple genders is and must identify as bi is a problem, other mspec identities existing is not.
I would love to see less identity policing from my fellow bis. People not finding bi to be the best fit is not an attack on you. Telling other people what their identity “really” is is just plain rude and we need more solidarity.