I've thought a lot about this. In the same way that governments can't stop crypto even if they tried, users can't stop governments from making their own crypto. In the world I see 10 years from now, each government has its own cryptocurrency, maybe large businesses/organizations have their own cryptocurrencies too. But that won't be something we think much about. It would make sense at that point for people to choose their own reserve currency such as non-inflationary bitcoin and have a smart wallet do the work of instantaneously converting whatever currency the user holds into whatever currency is required by the party they are transacting with.