What would happen if the plane had a mode - selectable by ATC or from a switch in each pilot's pocket or the purser's - that made it disable everything in the cockpit and fly itself to the nearest suitable airport with autoland?
It would be fine if you were sure the plane was otherwise doomed. The very existence of such a device would stop suicide attempts, and also the case where a plane took off from Cyprus and crashed for lack of pressurisation.
But I think it would be unsellable to pilots and passengers alike.