I continue to be skeptical about the idea of Sony trying to take ILC sales away from Nikon by limiting what sensors it will provide—an idea that has been debated on and off for over a decade. Sony would have to weigh wins and losses from the various ways that purchasing decision would change for people who would buy a Nikon SLR if they continue to have full access to Sony sensors.
Wins: customers who change to buying a Sony EVF camera.
Losses: customers who change to buying a Canon SLR with non-Sony sensor, or who stay with Nikon, now getting a model with a non-Sony sensor.
About break-even: customers who stay with Nikon and buy a camera with a slightly inferior model of Sony sensor, or who change to some other brand, most of which use Sony sensors.
My guess is that the high-end strength of the big two SLR systems, with their lens selection, AF, metering, and optical viewfinders, would make the losses outweigh the gains.