In this scenario $200k/year becomes the minimum income, since nobody earns less than that. It certainly wouldn't have the same purchasing power in that society

In this scenario $200k/year becomes the minimum income, since nobody earns less than that. It certainly wouldn't have the same purchasing power in that society as $200k has in the USA for instance, unless you take some kind of globalization effect into account, in which poorer foreign countries accredit this super-wealthy country purchasing power. Wealth is relative.