Hopefully they never take over the world, and we can stop this car nonsense. Having over a million extra people not killed by cars would be nice.
But how would you move around? Public transportation cannot reach everywhere. I would just stop seeing my family without having a car.
The harder question is how would you get from here to a world without cars in the first place. There are some pretty massive political and social hurdles to overcome. I don't think this will happen until we basically run out of fuel, unfortunately.