People are starting to realize that this definition is incompatible with rules against gender-based discrimination.

That's only if you believe that discrimination (selection bias) is the same as discrimination (categorizing). There's no apparent failure of logic until you start confusing them (eg "starting to realize"). If some people are starting to believe that the definitions are synonymous, they are wrong and will have to deal with the issues that naturally occur when you confuse ideals with reality. Generally some population group suffers for another population group to be supplicated in an arbitrary way.

This isn't about the kind of discrimination being allowed. This is about which groups we apply protections to. Do you also think I'm mistaken that a law defining marriage as the union between two people of the same race is incompatible with a law forbidding racial discrimination in marriage rights?

I am a person. And I am not starting to, at all.

I mean that there's a building legal recognition that laws against sex discrimination are incompatible with laws that discriminate against sexual orientation or gender identification. I did not mean that every single person on earth is aware of being at the start of a personal change.