Well to be fair there are more positives to cars than just cutting journey times. But I agree the negatives are massing hugely as the world's driving population pullulates.

As for human readiness to safely control a tonne of speeding metal, my position as a full-time motorcyclist makes me extremely confident that the average alleged 'driver' (actually: daydreamer, snot-picker, instagrammer) isn't even approaching the edge of the competence ballpark.