That's a false assumption. HN is much larger than you think, with people all over the US and all over the world. It has highly paid workers, lowly paid workers, people who don't need to work, and people who need to but can't find any.

We tend to make assumptions like "for the most part" based on the internal image when our pre-existing conditions meet a handful of striking data points—say the first 3 or so. And then we don't change it. But which data points happen to strike us are actually a function of our pre-existing conditions also. There are many other data points.