This is right. But tax avoidance has also been dramatically reduced. If you want to avoid tax, pretty much the only way to do it is to either move to one of th

This is right. But tax avoidance has also been dramatically reduced. If you want to avoid tax, pretty much the only way to do it is to either move to one of these places or find someone at a bank who will move your money for you illegally (this is pretty hard to do because the upside is often quite limited relative to the huge downside). So money is definitely moving back within home countries, and that is far easier to control. One point you missed is the importance of US financial control over institutions. The other plank of FATCA was the threat that the US would essentially block a bank/country out of the global financial system if they failed to cooperate. This kind of extra-territorial monitoring of the financial sector deeply annoyed everyone but..it was effective, and is a good example of a gain from US leadership of the international community (even Russia informally complies afaik).