Because of FATCA and friends, essentially all financial institutions in the world now report to the US and follow its rules. If you are not a US taxpayer, and outside the US, they don't directly apply to you, but they have already affected the regulations that do apply to you.
Funnily enough, I drew the opposite conclusion from grandparent's comment: To me, this is literally why the I'm-beyond-government-control crypto dream cannot work.
