At the end of the day, filtered water is a safer product than unfiltered and those who can afford to have it will do so.
1 http://health.hawaii.gov/about/files/2013/06/leptobrochure.p...
Backpacking everywhere in Switzerland people drank directly from these, and from streams And waterfalls, without filtration. And the Swiss are looking for any excuse to have something to spend their money on.
I’d never drink untreated water in Michigan. Michigan was a giant swamp. Near the top of a summit in Switzerland with no livestock nearby? Sure.
Switzerand is much smaller, so we have people checking on these regularly.
I always drink from these fountains, they’re all safe except the very few that have a “not potable” sign.
I wouldn’t drink from a random stream of water in the woods.