They lose nothing. Its their prerogative to initiate use of crypto but since they do not want to associate their people with it means they are not interested.
I don't expect anyone could reply in this manner or are you saying Bitcoin does not have any benefits? If it does, then both the government and their citizens have a thing or more to lose. What drives the agenda of some of them for banning Bitcoin is the decentralization of the coin, they want to overshadow every transaction thereby depriving everyone of their privacies. I will be opening a thread on this subject, this will help further in broadcasting what both parties would lose to more audience.