This is one of those articles where the comments are really interesting to read through. I see a bunch of comments who don't agree with the exact math, which might be warranted, but it seems at least directionally correct to me. However there's also a bunch of people commenting that this lifestyle isn't viable for some reason or another, that mainly just boils down to a personal preference those commenters don't want to live without.
But having read through most of the objections I still find myself enticed by this. If I mentally place myself in this position I think I could quite happily live a few decades without talking to anyone for weeks or even months at a time.
I'd still have my pets to give me companionship. Load my kindle up with a thousand books I want to read and just work my way through it. Pick up writing as a hobby and spend the rest of the time working at a gas station and fixing up the house and/or grow some food to offset the reduced income.
Healthcare is an issue. Doesn't seem like a viable place to grow old. Once you become too frail for physical work it's probably just time to die, which isn't great.