> The vast majority of civilian flights could be flown entirely autonomously right now.
This is extremely dependent on your definition of "autonomously" because at the moment they are not at all approaching autonomy.
At best, they'd be automatic, in the most rote way.
That's true. It'd be more accurate to say that the planes are capable, but that a lot about how the air transport system is organized would have to change to take full advantage of that - which we don't want/need to do, because an "automatic" system is too brittle, so we'd want skilled pilots on board, anyway.