I had some very interesting discussions with people at Boeing back in the 1980s, and also similar discussions with people at McDonnell Douglas in the early 1990s, about this subject.
At both places, they were confident back then, that they had the technology to build Commercial Airliners that could quite safely be flown without a Pilot, in fact they thought it would be much safer without a human Pilot.
There was only one thing stopping them all those years ago, they didn't think the Public would wear it.