Interestingly it's perfectly safe to drink tap water in Hong Kong. But tradition and fear of the government keeps water boiling alive.
https://www.mychinainterpreter.com/china-travel-guide/can-you-drink-tap-water-in-hong-kong/
As opposed to say parts of the US where you really shouldn't drink tap water but everyone does anyway. Flint Michigan looking at you.
What's crazier is I can explain the tides way better than I could explain what just happened with Russia's mutiny!