Hi!
Let's say there comes a scenario in the future where all/most governments in the world come to agree on criminalizing the use of cryptocurrency for the sake of the survival of fiat currencies (with the inherent inflationary problems from endless money printing etc).

Governments over the world thus shut down all interfaces between crypto & fiat, ie exchanges. They also put pressure on banks to refuse fiat transfers from exchanges still in operation & companies that accept cryptocurrencies as payment.

How would crytocurrencies survive that?