This is not accurate and not respectable
First and foremost I am a native Chinese person. This article is BS. 阴阳人 in Chinese is a derogatory term used against intersex people. I don't know about 红楼梦, or 贾宝玉 himself, but I feel like the author's intent for the character is probably more in the lines of "gender-non-conforming man". Of course, you can interpret the novel in your way, but the word is still very much derogatory and not an identity at all! In fact, the novel 红楼梦 is very rich culturally, so rich that an entire field of study is based on the novel, nothing is really concretely understood so please don't use anything in this novel as examples. I am not sure of the state of the intersex community in China, but most queer Chinese people use 间性人 as a more respectable term for intersex people.
-Noel