Interesting thing about Vietnam is that they often try to ban things but are never able to enforce it. Maybe someday the government will have enough money to start enforcing like China.
Vietnam is a small country and have small influence unlike China that has a big influence and has a nuclear arsenal that they can use to intimidate everyone including other superpowers. I think that banning isn't the answer and Vietnam thinks so with them now creating their own cryptocurrency, the regulations hopefully makes it favorable to both sides.