Earlier quoted context omitted.
The answer is likely that the treatment is expensive, and most people aren't drinking tap water anyway. My town completed it's pfas filtering system and water bill costs increased about 25% to cover it. I don't know one person in this town though who doesn't drink filtered water. That being said, I do still support the filtering.
Most people low and middle class people I have met my whole life drink unfiltered tap water unless there is a reason not to (safety or particularly foul taste). you might be in a bit of bubble. Not that it matter though as most bottled water is just bottled tap water anyway.
With added microplastics!