The trend in some organisations these days is to refer to PF (pilot flying) and PM (pilot monitoring) to more accurately reflect the respective roles. It has been suggested (CRM courses I’ve done) that to say that one is “not flying” infers you are superfluous to the aircrafts operation. An extreme I guess would be to say when coupled up both crew would be PNF. All semantics I guess and some would see it as a touchy feely sort of issue. Our operation uses the PF/PNF.
Brian