As long as there are countries that allow for tax avoidance it's not gonna work. If my income is in the 10s of millions I am better off paying a few millions to some firm to handle every single thing for me to hyper optimize my life. They make you change residence on paper and buy fictitious tickets to prove you have been in country x at least y days during the fiscal year, and much more. You still end up saving way more than paying 20/30% of taxes on those 10s of millions.
There should be a global minimum tax, but trying to make every single ruling party in the world agree to that is a fool's errand. I think that what the little that got leaked by the Panama's papers few years ago is just the tip of the iceberg.
Since 2019, large corporations the world over have been forced to open up their books to fiscal entities in their respective countries. Every country could tax what these companies earn in their country, and also add some penalty for evaded taxes booked in other countries.
We can do the same with billionaires and their assets.
The tax evasion industry (for corporations as well as for individuals) needs way more regulation and penalties. These firms inflict a net negative cost on society.
There should be a global minimum tax, but trying to make every single ruling party in the world agree to that is a fool's errand. I think that what the little that got leaked by the Panama's papers few years ago is just the tip of the iceberg.