It means religious faith is best sustained in societies where there is little individual and societal health. Christians will say this reveals the human tendency to throw off God when we don’t need him. But a much better explanation is that a God who can thrive only where there is little societal health must therefore desire for us to have little of it. If that’s so, he does not want the best for us. So at the very least this provides disconfirming evidence that such a God cares
