>For the wealthy, a high cost of living is a choice to live where they want.

To an extent. I think some of them might not mind living in less expensive rural areas if they didn't need to be in proximity to their workplace or common areas of business.

We aren't exclusively talking ultra-wealthy billionaires here, I imagine the article is mostly concerned with the more common wealthy upper-middle class workers like programmers, doctors, etc.

It does make a few differences, ie. plan to save a lot and cash out at lower CoL places.

Because then you can show that controlling for location, Asians don't make more than whites. Asians who live in high cost of living places or low cost of living places make the same as whites living in the same locations despite having more education. This analysis is a rebuttal to the argument that Asian median income as a whole being higher than white median income implies that America is a post-racial society where working hard will result in equal reward regardless of race.