They can't afford to block crypto, even for their own citizens. Crypto can flow from even the smallest gaps. If Chinese citizens are unable to disburse funds to local banks, or block all local crypto exchanges, they can withdraw funds via Credit Card. Will they block Credit Cards too? There are many other methods for withdrawing funds from crypto. The water will flow to the lowest place through small slits. I think there is only one way to block crypto, which is to block the internet network. Lol