It's definitely more of an emotional issue than a technical one. I think there's even a case to be made that machines will someday fly more safely than people. There are plenty of aircraft mishaps without robot pilots and, as the Safety Center is quick to point out, most of them involved pilot error.
For every time a pilot pulled some outside the book, intuitive solution to an emergency, and saved everyone there's that airliner that crashes into the ground because all three of the crew are staring at an inoperative light bulb. Computers don't get drunk, computers don't have heart attacks, etc., etc.
It can be done. I think someday it will actually be the more logical choice, at least from an efficiency and safety standpoint. The question will be if we actually ever do it.