[verdverm]

You don't ban the blockchain, you make it illegal to use the coins. Then the network loses value and mining doesn't pay off. If you don't do KYC or AML, you will likely become part of the banned list.

Also you can look for energy consumption. Towns in upstate New York are banning new permits for mining. So it's already happened.

In short, society has certain expectations and if you violate those there will be consequences. Govt and laws are always behind the publics will, so it's coming for cryptos. Which survive is the real speculative bets that will pay off