The idea that Earth being accessible to everyone at infinitely faster speeds is not a dark age. That is a golden age. It's sad that you've confused the two, but it's modern propaganda at work. The environment is damaged by humans. Not cars. If we banned cars, people would still ruin the environment, just in different ways. But that's cutting the nose off to spite the face.

The truth is, cars are, for the most part, amazing pieces of technology that allows nearly every person freedom of movement. You aren't going to change that without creating something better.

It seems like electric, self-driving cars are a possible dream, albeit even close to a pipe dream. Cars none-the-less though.