With the distribution of wealth going the way it is, it will only get worse. We can talk about this as much as you like but a huge segment of the population can't afford the basics of living in the US, much less pricey, auto-driving cars.
What makes you think they will be pricey? It costs a lot to invent the technology. It would cost very little to actually deploy it. About as much as a good car stereo.
The poor in the United States can't afford a lot, but they can afford to use the largest supercluster of computers to perform distributed data slice retrieval queries running on billions of dollars of computational and communications infrastructure. We call it "google search." The most powerful technologies tend to become ubiquitous and inexpensive. We don't all have jetpacks or yachts, but the majority of Americans have email. Of course the very, very poor don't even have consistent access to the internet, but while that's unfortunate and should be addressed, that's not going to slow or stop technological progress.
In any event, thinking that poverty will prevent the adoption of technologies like self-driving cars seems inconsistent with recent history. The one that saw the development of iPods, iTunes, smart phones, tablet computers, Netflix, email, twitter, facebook - poverty didn't prevent any of those inventions from changing the world in significant ways. Who can afford an iPad? Only a toy of the rich? There are schools handing them out to students, and other schools handing out other tablets that wouldn't exist were it not for the introduction of the iPad. Only rich people tweet? Doesn't change the fact that twitter changed the way news propagates in the world, whether you are rich or poor.
When world society and governments collapse because of "how bad it is getting out there" the only survivors will be the people that stocked up on supplies purchased from Amazon, that novelty internet book store that won't change the world because how many people can really afford to spend any of their hard earned wages on a book.
This is not to minimize the problems of the world, but rather to dismiss completely the notion that you can predict what technologies will change the world from a social justice perspective. It might be nice if that were true, but its never been true since the first man bashed his first victim with a rock tied to a stick. Technological progress does not, and has never worked that way.