A digital currency (like digital yen, dollars or euro) can be shut off. Yes.
Bit crytpto cannot.
Now, the government can cut off electric power and internet access.
But if we get to the point where power and internet service is decentralized.....then.....crypto can’t really be stopped.
Crypto can effectively be rendered too cumbersome to deal with.
If crypto currency becomes illegal for retailers to use then there is no one to buy from no matter how many bitcoins you have.
If you cannot walk into Walmart and buy something with your crypto currency then it is of limited value.
Perhaps one might move to Singapore or some such place and redeem their bitcoins and retire in luxury...but how many people want to move to Singapore?