I would imagine the big thing is air quality. India regularly tops air pollution lists: https://en.m.wikipedia.org/wiki/List_of_most-polluted_cities_by_particu

I would imagine the big thing is air quality. India regularly tops air pollution lists: https://en.m.wikipedia.org/wiki/List_of_most-polluted_cities_by_particulate_matter_concentration https://en.m.wikipedia.org/wiki/List_of_most-polluted_cities.... You can’t totally avoid outside air. Anecdotally I remember hearing of Chinese people moving abroad and having their chronic asthma clear up almost immediately.