Identity politics has been the bedrock of American politics since before the Mayflower Pilgrims[1] landed at Plymouth rock, and hasn't ever stopped for even a day. Any claims of recency says a lot about the speaker rather than reality.

1. That they were "pilgrims" is enough evidence. All the jey moments in American history are underpinned by "identity politics": the the 13 colonies, manifest destiny, expansinf west, the declaration of independence, slavery, civil war, reconstruction - all of it.