I don't think I agree with the existence of non-binary genders...not sure though
If I understand correctly, the argument put forwards it the difference between Biological Gender (of which there are 2) and Social Gender. Gender roles in society and stuff.
I think the general idea is that there is a spectrum of what "Gender' you are as a person in day to day life, and what people are doing is defining markers along that spectrum so that you aren't simply black or white Male or Female. They use stuff like sexual preferences to help define those markers. But I don't know enough to comment on how they actually come up with all their new Genders.
My only issue is that once you start creating new labels/groups to capture those who don't feel strongly as either of the two existing labels, then eventually some people are going to pop up who don't feel they belong to any of the new labels either, thus creating even more labels, and so on and so forth till basically every individual is their own gender and the whole concept becomes meaningless.
One should never publicly don the mantle of being "good", and rather be known for your unpredictability. Anchoring expectations only make your efforts and ethics go underappreciated.
Edit: CMV.
What if 'anchoring expectations' helps bind you towards behaving in a certain way, when without having any reason to do so, you may be tempted to behave otherwise.
Example - I don the mantle of being a Good Person. I see someone in need of help. I know I can help them, but at inconvenience to myself. I'm tired, worn out, would much rather do nothing and go home. But I have donned this mantle, therefore I now have something to lose if I don't help out. Therefore, I put in the effort and inconvenience myself to help this person out and do something good.