The trend of people forming deep tribal identity around political affiliations and institutions. Speech then is first and foremost performative signaling of your in-group affiliation to the good group or the evil group. At least that's the lense any speech or action is looked at within identity politics.

Thanks for that clear explanation!

You say trend like it is a recent phenomenon and not something that has been happening for centuries if not millennia.

That’s true. Identity politics is just a new name for it, but we did use to burn people at the stake for the same reason.

it would be dishonest to ignore the fact that "contemporary identity politics" kicked fully into gear as a direct response to #Occupy—and its objective was & continues to be successful

Contemporary identity politics are at least in part a response to the contemporary "occupy" movements, sure, and that's pretty much by definition.