I'm not making a statement about those people, but what I said still applies: the opportunities on that list are available in SV, and a small number of other places in the US. Not in Saigon or Amsterdam -- at least not to a large number of people.
HN is about news that happens mostly in SV, or is relevant to it. It's about startups -- high-risk, scalable businesses -- and SV is where they are (at least, many, many of the successful ones are). I'd expect that a solid majority of the readership is based in this area too.
My premise is this: people who choose to live and work in SV have huge opportunities that exist (almost) nowhere else. Sure, you can setup a consultancy and dabble in a few side projects while you make your way around the globe and have remarkable experiences.
But let's not pretend that, if you choose to do this, you are exposed to the same opportunities as the rest of us -- you're not.