If y'all have played Bioshock... Rapture was a libertarian fever dream. No taxes, no regulations, everyone free to do whatever they want.

Look how that turned out.

(also I never really understood how that could even work, even a regular city needs constant maintenance, one under the sea, exponentially more so. Building it alone costs a fortune, maintaining it too, and as a closed ecosystem, and you either need to fund the maintenance somehow, or use slaves - admittedly, Big Daddies were indeed slaves but that came later on. Without taxes, nobody cleans the common areas, nobody fixes the ventilation, broken glass, etc., because there's no money pool to pay the workers from, buy the raw resources and tools from, and so on)