Here is the thing.
The human brain works in concepts. Prototypes. Classes. Ideas. Groups of things that are similar, and things that separate them.
Gender is ultimately a biological class describing reproductional role. For some reason the biology on our planet has two of them, one specimen of each is needed to produce additional ones. It’s not about how you dress, how you sing, and so on.
Even if the word gender is moved to mean your preference, a new word will born, that will describe the biological class describing your reproductional role.
It’s really pointless to fight it.
As for classification. There are pine trees, spruce trees and cherry trees. They are different. No matter how that pine tree feels like a cherry, it’s still a pine. Why? Because we defined it as having needle-like leaves, connected to the branch in groups.
Now, I don’t mind if that pine dresses as a cherry. I may find it weird, but ultimately, it’s not a problem to me. Really!
However, if that pine tree decides to shout “I’m a cherry”, my natural, obvious, sensible reaction is “no, you’re not”. And if that pine throws a fit about it, starts shouting, shaking and all, is it a problem with the classification or is it a behavioral problem with the pine?
There is a perfectly appropriate way to go about it: I’m a pine, yes, but I really like to roleplay as a cherry tree. For reasons, I also love to hug them, and shower in their petals, and wonderful summer leaves. If you don’t like it, please move along, I mean no harm to you.
However, if you force people to call pine trees spruce because it hurts your soul, it’s really a problem with you.
Normally, people don’t really care. They might have a weird look or something, because it’s abnormal biological function, or they are sad because their kid will not have children so their lineage is going extinct. But what’s happening is inciting a war by forcing it too hard.