The real question is do we want historical city centers to become attraction parks only for tourists or do we still want people to live there.

AirBnB and the boom of private tourism rental is transforming city centers in the former. New housing is constructed, just on the outskirts of these cities and push people off the city. This is bad for the dymamic of the city, this is bad for the environment when people pushed outside of city centers usually have to resort to drive to go to work...where they used to live, this is bad for kids and becomes a health issue when kids can't walk to school anynore and this is even ultimately bad for tourism itself as these places lose their soul and every single restaurant becomes a shitty tourist trap where no effort is needed or made in term of quality and service.