Don’t Hang Up
I think it might help in answering your question if we separate the two jobs crews perform:
1 Steering the aircraft (controlling speed, altitude and heading)
2 Operating it (every other function).
For my money the current technology can/could cope with all steering since it is already certificated for automatic landing – arguably the hardest and most demanding steering function.
As to operating the aircraft (not just dealing with ATC) the crew will have to intervene throughout the flight in many different ways depending on the type of flight, the type of aircraft, the type of company, the type of passengers etc etc. In my view there is no current technology that can carry out these functions without considerable crew intervention nor is there likely to be in the foreseeable future.
Indeed I would go further and say we should not waste money on trying to automate these other functions (other than ATC aspects) because humans are so good and flexible in carrying out such duties. Plus we will always need people locked in the front or nobody would (sensibly) ever get in the back.