I think bitcoin can only boost the economy of a country. What I mean by that is bitcoin can help boost the economy through collecting tax from individual traders and companies as well and I see no way for bitcoin to break the economy of a country unless through looting by top government officials and that's not bitcoin, that's called corruption.
I don't know what is your point about bitcoin collecting tax. Bitcoin cannot collect tax but the government officials can tax the people who uses cryptocurrency in their country. Cryptocurrency taxing is already happening in some states and it is a good move because it is a sign that the government are also paying attention to cryptocurrency.
Exactly if the same thing happens in the countries who have banned crypto will get benefitted. The government as well as their people's, well this will boost the countries economy too. Political parties have banned this digital currency for their good will. Government administrations need to understand that this is very unique and make this legal service to benefit their own people.