Don’t have a ref but heard that it’s been safe for quite a while but they keep the pilots around due to consumer fear rather than actual improved performance. Curious if anyone can confirm.
The less you can change about the product and environment, then automation run slower and less effectively.
Air liner operations could be automated, but the minimum equipment list would be more stringent, the destination airport would not be able to take any equipment out of service for maintenance, visibility minimums would increase, takeoff and landing operations would require more slack time.
Besides all of that, the owner of the airplane would still want to have some crew on board.
In short, it's not worth it yet.
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There is also the paradox of automation: Automation generally makes the hard parts harder and the easy parts easier.
It's very cool stuff, technology wise, with potentially significant redesigns of cockpits, etc.
But the main thing is the plane basically needs to be able to operate just about entirely autonomously (especially during critical flight phases) in case the pilot is incapacitated.
In theory, once SPO is solved, autonomy is almost solved.
Cargo flights over oceans and (mostly) unpopulated areas might be a valid use case for SPO. Cargo pilots have always been considered somewhat expendable.
At the very least, I'd say it's at least two clean-sheet designs away (which I'd guesstimate at 30 years).
I'm a bit partial to it because I did a brief stint in the Airbus realm. Autonomy for airliners is an interesting set of challenges.
Look up the Airbus ATTOL project's first automated takeoff a few years ago.
Also, there's virtually no automation when it comes to interacting with ATC.
I just followed what my CFI and Cessna's manual for the C172 said (which iirc was giving input to rotate at 55kts).
It's fun to see/feel planes do stuff "on their own" (eg making them oscillate, or level on their own, or feeling ground effect, or even your own wake on steep turns) but it's not something you'd want to rely on (maybe with the exception of ground effect on short field takeoffs, but I digress).
It wouldn't be that hard to fully automate a flight from gate to gate when everything works perfectly. But the various failure modes, human error like airport vehicles entering active runway, all that requires human backup. Self-driving car can just stop to the side of the road and turn on emergency lights if its engine fails, with a plane things get much more complicated.
Cars can drive around without needing to talk to other cars or controllers.
Check out the Cirrus Autoland feature in their aircraft. They are all small personal aircraft, but the tech is pretty cool. Will talk to ATC and fully auto-land for you in the event of an emergency where the pilot is incapacitated.