There are already whole fleets of autonomous planes in the air. They have autopilot. The only difference is that when something goes wrong in the air, you can't just pull over and get a tech to the plane. You need someone already in the cockpit who knows what they are doing.
I do think that pilots are commoditized, but not to the extent that they are interchangeable in this manner. The industry is way too heavily regulated for this to ever work, and for good reason.
Honestly, well before something like this would come to pass, there will be whole fleets of autonomous planes in the air, thereby avoiding this scenario altogether.