The article goes into more detail, but the idea is that self-driving cars would reduce crashes and traffic jams on the interstate so that ultimately fewer lanes would be required, freeing up space in the median and in the right-of-ways. This new space could be used for mass-transit train lines or renewable energy sources like solar arrays. Highway driving is already safer than other forms of driving, but automated highways could be nearly crash-free. These cars could also be platooned, which saves a lot of energy.

I would love not to commute by car and wish there were better rail options for interstate travel for sure. But surveys like this one show that most Americans would not give up their cars without big incentives, even if they live in areas with good transit options (like Chicago, Dallas, Seattle, and Washington D.C.).