And only really wealthy people can afford to stay in a 5-star luxury hotel. The underlying mechanisms are the same: when demand for a resource is greater than supply, you can either artificially limited the demand by some controlling body, or let the market bring them into equilibrium through pricing signals.
By electing a socialist government the people of Berlin have indicated that they don't want their city to become a five star hotel. Simply letting the market take control is therefore not an option.
I understand it worked in Vancouver where it was tried. I've not heard news that London or Paris has tried.