Upvoted, because you make the case well that we shouldn't identify with sides when discussing issues like this.

But you're not really using "Taboo" in the sense that Eliezer described. "Sides" do exist as social phenomena. They are a certain sort of coalition that people group into when they engage in public discourse. As you say, sides exist for non-truth-tracking reasons. However, like race, we need the concept of sides to talk about social dynamics, so, like race, sides exist.

(Of course, they exist as nothing more than certain configurations of the pieces of the stuff out of which reality is made.)