I know all 7+ billion people on earth don't have cars.
But what about 2 Billion people having cars, Imagine if two billion + people had these, would travel be any safer ?
Or would everyone on the ground be in even more danger because there are no safe places to walk when cars can drop from the sky. I would say we're still a ways off from seeing this in real life. Maybe a decade before it commonplace.
I think we are now at the start of a new era, and in a few years the earth will be just a crazy place: what we see in the films after a few years will become real : )