This is why broad averages aren't always the most useful statistic. The number of complete mirrors required to make the data trove fairly robust is much lower than the number of people in the world, and the prior commentor's qualifier was "people reading this", which is likely a biased sample and includes many people working in technology in the richest countries in the world. It's unlikely that said population's income is clustered around overall national averages, and only a relatively small number of outliers are required to set up adequate mirroring.

They said "many people reading this" and HN's biggest audience is US tech workers. It wouldn't be ignorant to say that many US tech workers can afford that.

The table doesn't list the same as the map. For instance Norway and Sweden is included in the map, but not in the table. And I don't think the average reader here should be compared to the average income around the world. Rather a top single digit percent.

Off topic but I didn’t realize you could save that much! Why are externals less expensive?