Earlier quoted context omitted.
But also, the fact that it was impractical is itself a metaphor -- it turns out many of the things they thought would be cool and futuristic were actually impractical when you get to the details.
Sure, but that's besides the point. It's sort of like that meme about "The World If " (example: https://i.kym-cdn.com/photos/images/original/001/394/070/7f2... ). It features over the top flying cars and infrastructure because it's trying to make a point. When one says "we could have had flying cars, but instead we got X", that's the underlying concept. Whether or not the flying car is "practical" is kind of besides…
http://eduard-heindl.de/energy-storage/energy-storage-system...
Well, we would get cheap energy storage and cheap energy. No promises of a superior future, just a cheaper future.