We've had tremendously advanced autopilots for a long time, but there have always been people up at the front, supposedly in charge.
It's the difference between getting on a bus with a guy in the drivers seat who has auto-braking so he doesn't accidentally rear-end someone and getting on a bus with no driver at all. People are OK with the first, but less likely to be OK with the second.
I'm not saying it's rationally correct for people to behave this way, but they do behave this way.
For one thing, I think it means the transition will be easier than most people fear. As we get more and more automated, we'll start making entire flights from gate to gate without human intervention. At some point, somebody will say, "It's been three years since the last time a human airline pilot actually did anything, so clearly you're all comfortable with being flown around by a computer, let's take that final step" in a convincing manner.
Like autonomous cars, autonomous airliners have been steadily sneaking up on us for a while, and the first fatalities have already happened. It's a smooth function, not a pure on/off.