No becuase citizenship implies deep cultural and philosophical values as well. You cant switch those that quickly

Another reason is that the responsibilities between citizen and society are fulfilled on a long timescale. A society will educate you, and then you need to contribute to the economy in that society to pay it back so to speak. Technological innovation, military service, rasing future citizens. Any of these things can only happen on a long timescale so quickly switching citizenship doesnt allow that contract to be fulfilled