Good point, that's a reason to wonder.
I think this "social scurvy" thing is completely spurious, though. Some people get anxious when alone, probably including the author, hence this post justifying socializing as something everybody else needs to do. Because after all, being unsociable is socially unacceptable. But what's this based on? Being alone is correlated with ill health - well, people will tend to stay far away from you if you have the plague. One study found that people's desire for company rose hardly at all after a mere ten hours, is that surprising? I mean, make it a month, ask me again. This isn't evidence for socializing being necessary. Then we have tribal New Guineans chattering constantly about "who urinated when and where", but just because they're a model of a close-to-nature society doesn't mean the things they do are right, or healthy, and it doesn't mean we have to. (I might also wonder how close together people in tribes are in terms of genes and houses. If they count as "household", that's disqualified from being true socialization in this theory anyway.)