Cost of technology
As stated 'pouring millions -- if not billions -- of dollars into developing self-driving vehicles' and knowing full well that they will be pouring even more in the future to regulate, develop, market, etc.; what is the possibility that anyone on this planet, save a few billionaires, could even remotely afford one of these? The Prius and other green cars are priced at a level that does not save the owner any money. Electric cars are not a just-do-it as their cost is out of reach for most and will never have any real ROI.
We know from the medicine industry that drug costs are a direct reflection of the cost of research and development. They are protected for X years before a generic is available so that they can recoup the cost of invention. Using this same logic, minus the protection, these cars are going to be expensive. Very expensive! Probably way out of reach for most people and well beyond my meager income level. I will not be able to afford a $60K+ autonomous driving car. Hey, I have a hard time justifying a $25K vehicle. They just are not worth that price.
Cars have gone up dramatically in price due to regulatory intervention and the addition of useless, unneeded and many times unwanted electronic crap. Adding $500 dollars worth of GPS and backup cameras to drive the price of the car up exponentially is ridiculous. Personally, if you cannot find your way to and from work, local restaurants and other local locations without GPS, you probably should not be weilding a 4000 lb car. (Ok - maybe thats mean, but I see people who cannot get 2 miles down the road without programming their destination... just sad!)