Even with full automation, someone, somewhere, would have to be in charge and make critical decisions. A true AI capable of dealing with things like WX deviations, the NAT system, compounding mechanicals, problems with the pax and crew, ATC, etc (a list a mile long) simply isn't there.

Assuming the pilot is driving the airplane while wearing dirty tighty-whiteys from his PC in a living room, it'd require immense bandwidth. With thousands of aircraft airborne, you'd have terabytes per second streaming all over the globe. What happens with a solar flare? Or intentional jamming?

Do we really want to trust our lives to a RADIO link? Because in the end, that's what it would be. There's no other method of remotely piloting an aircraft.