If your information doesn't have those error bars it is just a feel good headline to make someone feel better about themselves by putting others down - this is EVIL and you shouldn't fall for it!
There are far too many subjective parts of quality of life to ever put a single ranking on them.
But would everyone except for "obscenely rich people" be better off somewhere else? If so, then where, and why aren't they leaving by the tens of millions for those places?
Because life is messy. Because leaving is expensive. Because being accepted into a successful country requires opportunities and circumstances.
The idea that the US is "the best place to live" is a persistent cultural myth. It's mostly good for a lot of classes of people, but even that's changing as of late.