I don't think you do know what it is, and I don't think being queer inherently imbues you with that knowledge.
Queer Theory is a philosophy (or theoretical framework) about language (as with all postmodernist philosophy). It's not a "study", and while queer people can be a subject, it's not its primary object.
Furthermore, a book written by two liberal scholars is not a "far right nonsense book".
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Why do people insist on taking hard positions on topics despite never having read the material?