The biological basis of gender is not a belief, but an objective, verifiable fact supported by multiple lines of evidence. No matter how loud the screams of the gender-centered mentally ill, no one has ever changed their genome or physical attributes by believing them to be something they are not.
Your take? :-)
Agreed. Gender is the sociological manifestation of biological sex. There may be rare pathological deviations from this norm but it is not something that the whole of society should be forced to accept as a desirable or viable alternative.