All the technology in the world cannot fully replace an incapacitated pilot, so single pilot is a very long way off. Technically possible does not mean safe, economical, insurable, or certifiable.

They would have to build a full auto system, and then fly it two pilot for a long time to demonstrate it's level of safety, and then go single pilot. Who's going to pay for that? Hint: Not airlines, they only buy planes with equipment which is regulatory or will provide an immediate and predictable cost savings. Management gets paid to enhance shareholder value by next quarter, not by next century.