It was the most amazing, refreshing, delicious water ever. While there was almost definitely a psychological component to the initial taste (we were used to iodine flavor, were tired after about 3 days of hiking, and the area was beautiful/it looked like something out of a commercial for mountain water), we were there long enough and it continued to taste good enough that I'm positive there was something else going on. I think it had something to do with the rocks, a light amount of healthy bacteria(?) and it being fresh snowmelt.
I'm in no way advocating for shipping water across the planet, and I don't think you can bottle that up or recreate whatever was going on there at scale, but there's definitely a legitimate, big range of difference in water quality. I'd bet good money most double blind taste testers could easily distinguish between legitimately fresh cold mountain water and refrigerated water that's been sitting in an aquifer and then a plastic bottle for a while, even if you matched the salt content. But you'd have to go up a mountain to do that test properly. I think it has to be like right out of the stream to make the biggest difference.