He set a goal of being totally self-sustained, and achieved some amount of it, while eventually recognizing that the cost of such an experiment was higher than he had initially thought. The whole article ends with him coming to terms with the fact that society is necessary in so many ways, and that we can perhaps achieve sustainability easier as a collective, than as an individual.
It's so easy to read the story from the comfort of your chair and criticise, isn't it?
Yes, and often the validity of the criticism bears no relation at all to the comfort of the chair of the author. Weird, huh.
Living off the grid is very practical. There is land on the big island or in the desert where you can get really cheap. Imagine owning a house (quality depending on effort you put in) in a warm climate for 20K. It's actually possible.
I would probably go with "Saying hi to the owner of the local general store" as a minimal amount of human contact. But then, I'd rather talk to shopkeeps than baristas even on a social day.
The US has lots and lots of cheap land with utility hookups if you don't care about things like high paying jobs.
I'm not sure if any self-sustaing fan would want that.