This largely depends on which government. For the US or EU the choke point is dollars or euros. They just make it illegal for any bank to do business with any o

This largely depends on which government. For the US or EU the choke point is dollars or euros. They just make it illegal for any bank to do business with any organization that accepts said cryptocurrency. It won't "destroy" the cryptocurrency, just make it unviable as a currency. If you want to see something similar in action really dig into the nitty gritty details of how sanctions are used via the international banking system.