This was fascinating and it's very much a complicated issue that needs addressing pretty sharpish. I'm worried any good faith has gone out of the discussion in a way that isn't helpful for marginalised trans-children or women fleeing domestic abuse.
For what it's worth, I think identity politics is very much the play thing of the upper-middle class. It's a way to assert power, particularly in the arts and usurp the previous generation of upper-middle class folks. We're seeing it across theatre, across TV and it seems to be across publishing too. Marginalised voices that are being discovered are often from the same class and it's a real problem - because it doesn't reflect the views of the vast majority of people in the country. It's a creative and ideological dead end and it's slowly strangling both the arts and reasonable discussion.
Also, Bev is correct. These pile-ons do happen. :o)