Very interesting reading… Um, perhaps if I start here: My community does not recognize only male and female, as in the traditions of my tribe have a different grouping of categories. It is troublesome for people in my position to view ‘transgender as umbrella’ dispassionately as we are not trans in the western, specifically US, take on that term. So my bias is in reading with a “Two-Spirit” eye.
That said, the result was in reading this I did not see ‘Trans itself is a part of a binary categorization and is therefore flawed’, what I read was ‘Trans is being used as way to establish a new and equally artificial dichotomy, equally as damaging as the previous’.
I concede it’s quite possible you’re reading is the more correct and I’m mischaracterizing Williams’ argument. Just wanted to throw in my own two cents in case it’s helpful.