There are places in this world that are just outstandingly amazing and desirable. Why is it anybody's duty to enable additional people to immigrate into such p

There are places in this world that are just outstandingly amazing and desirable. Why is it anybody's duty to enable additional people to immigrate into such places? How many more people should they provision for? At the end of the day it is not the Hawaiian government's job to enable the whole world to come and live there. Being too hands off may lead to unfairness in some ways, i.e. gentrification, but at least discouraging investors seems a step in a direction of helping the less wealthy.