In the end this debate boils down to whether automatics can be demonstrably safer than pilots in flying an aircraft.
Of course pilots (of which I am one) will tell you that only they can consistently control an aircraft safely and that they will avoid "stupid" errors that a computer would make when faced with a situation that it hasn't been programmed with.
However, the fact is that pilots make dumb-ass decisions all the time, and fly into the ground on a regular basis. They even shut the wrong engine down on occasions, so that the aircraft crashes when it wouldn't have done had the computer been flying it (Kegworth).
Once the general public can be shown that actually it is safer for pilots not to be involved, that is when the acceptance of pilotless aircraft will come to pass. IMHO. Especially if you tell them that a remote link is always there to cater for "unknown" situations.
We are still talking a couple of decades mind.