Because that’s not how it works
Believing male and female are the only genders is ignorance and hate, not an opinion
Being homophobic/transphobic isn’t an opinion, it is simply ignorance. And nobody is entitled to an opinion, your right is to an informed opinion. Homophobes/transphobes are people who disagree with others living their lives how they want to and not hurting anyone by doing so. Homophobes/transphobes are ignorant people against progress, living in the past.