“Every digital app developer, no matter how humble its offices or how small its staff, almost automatically becomes a micro-multinational, reaching global audiences with a speed that would have been inconceivable in the first machine age. In contrast, the economics of personal services (nursing) or physical work (gardening) are very different, since each provider, no matter how skilled or hard-working, can only fulfill a tiny fraction of the overall market demand. When an activity transitions from the second category to the first the way tax preparation did, the economics shift toward winner-take-all outcomes.”