We'll be very close to unmanned airliners then.

But single-pilot airliners are a lot further off than you think...every year a handful of airline pilots suffer incapacitation. In a single-pilot world, that translates to a handful of smoking holes each year, maybe four or five. The public wouldn't go for that.

To make matters worse the the bottom half of the seniority would get discarded in that scenario...but that's not the group prone to sudden-incapacitation! Unless the airlines could get the FAA to limit single pilot ops to age 39 with invasive medical exams and tests cardio tests.

So the single-pilot airliner would have to be fully autonomous anyway (with all the costs and challenges I mentioned before).