3 ideas
A society that is run by rigorous logical consistency will follow its principles into inhuman results. A society run by reasonableness, a sense of what feels humanly sensible in the specific case, stays livable because it lets common sense override any doctrine carried to its extreme. The island's institutions are judged by whether they feel reasonable to ordinary people, not by whether they are theoretically pure.
The modern West treats leisure as a reward earned after productive work, which makes busyness the default and rest the exception. The island reverses this: work serves leisure, and leisure is the time spent on conversation, friendship, and enjoying life, which is the actual purpose of a civilization. By this measure, a society that grows richer while its people have less unhurried time has confused the means with the end.
Imagining a community that grew up cut off from modern civilization turns that civilization into a variable instead of a given. When outsiders see that a functioning society lacks things they considered inevitable, such as constant striving or ever-expanding technology, those features show up as choices, not necessities. The lens gives a practical test for any modern habit: would a sensible people starting fresh choose to adopt it?