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?
Tell me, exactly, why does the study of queer people mean diversity and inclusion is bad?
Not even going to touch your idea that colorblind racism isn't racism.