He mentions 2 decades ago it being fine, so I presume not India. The advice to only drink bottled in India was common 20 years ago too.
These days its so sad to find every shop ordering a container of filtered drinking water. Earlier it was available through taps. Now no one trusts tap water.
Most urban households have some kind of filtration system in place. The water supply infra is quite bad, with frequent contamination due to leakage.