> I assume that this is a just alarmist journalism, since water for tea/coffee is heated to boiling ...

Boiling at elevation is different to boiling at sea level.

To kill Cryptosporidium (etc) you need a rolling boil for 1 minute (no one does this) ... and that's at sea level. At > 2km up you need to run that for > 3 minutes (and absolutely no one does that).

And all this is before I even get started on the woefully uncivilised idea of using 100C water for green tea.