How's that working out for the people in Flint? They still don't have clean water. Is it like the fairy in Peter Pan where if you believe hard enough the people in charge will magically become competent?
Obviously there are limits but having your water tested from time to time isn't bad advice.
Another thing I do is test my kids toys for lead, and it comes up positive roughly 1 out of 15 times. I could trust that the government and the big box store makes sure that never happens, maybe you do, but I do science so I can know instead.
This isn't a binary between complete blind trust and "living in the woods", my point is if you want your kids to have clean drinking water the best way to do that is test it yourself. If you trust the US government to provide it for you, you'll end up here crying about how they abused your trust for the ten thousandth time and be somehow, inexplicably, surprised.
Water quality is primarily the responsibility of states. They generally follow EPA standards, but there isn't some EPA guy visiting your local water plant, it's the state.
It's wild that people think water quality has gotten worse over time.
Unfortunately the entire existence of society since humans were apes living in trees relies on this whole "trust" thing