The overall article is fine, but I really don't agree with its understanding of binary as an identity unto itself, and the article assumes too much that the way nonbinary people relate to being nonbinary is perfectly mirrored in how binary people understand binary identity. Binary isn't an identity I've ever seen anyone identify as as an actual identity, it's just the state of not needing more than one word to explain your gender identity. And especially for gay binary people, people of the other binary gender don't really have anything to do with their identity or experience of gender, romance, sexuality, etc any more or less than nonbinary swarm gender people do.
I don't think he'sthey're assuming anything he'sthey're just using the term binary as a set/group that includes the traditional man and woman genders. Sure maybe no one uses it to describe themselves but that doesn't mean that the word isn't useful to refer to the "traditional" genders, which he uses to contrast with non-binary.
Your conclusion is exactly what the Author tries to get at, that non-binary spectrum is diverse in many aspects.