Lot of countries do not allow to use crypto currencies and they discourage using them. However as far as I feel, trading with crypto is not that harmful for the economy of the country. As an example, if a person has Eth and someone from another country needs to buy Eth, that buyer needs to pay the seller in terms of dollars. Then that seller needs to convert that Dollars to his native currency which means it creates a the demand for the native currency and increase the value of the currency. May be the government is unable to add a tax on such transactions but it is beneficial for the currency used in seller's country.
What do you think about that?
What you exemplify is one of the reasons why the state does not accept crypto, if its citizens use cryptourrency to transact it will only increase the crypto demand and the government does not get anything, the government wants reciprocal benefits (no tax no profit and not be allow). One more thing about unilateral thinking by the government, as if crypto is there to help with crime is the reason why there are still many of the lay people not using and interested cryptocurrency.