This is basically describing the Cayman Islands. Or, to lesser extents, UAE or Malta (e.g. https://taxjustice.net/2026/02/24/malta-the-eus-secret-tax-s...).

The problem with this warm Galt Gulch idea is that someone has to do the actual work, and if the top level government is just a corrupt sinecure designed to shield the corporation from actually paying taxes, then nothing works properly. Comfortable island living is also surprisingly expensive, you have to import everything.