I suspect the isolation misleads the subject. The subject loses their modes of interaction with civilization, that make civilization so far superior to the low-

I suspect the isolation misleads the subject. The subject loses their modes of interaction with civilization, that make civilization so far superior to the low-population density existence of prehistoric hunter gatherers. Without those modes, the subject returns to civilization seeing only what civilization deprives one of: the great expanses of unspoiled wilderness. And that produces the existential crisis and criminal insanity of TK.