Governments can, and most likely they will, issue their own cryptocurrencies, but they can't force all the people to use them. Fortunately, we are not living in North Korea, where that would be possible. Whatever new crypto is issued, Bitcoin is here to stay, and I think most people will prefer using it instead of cryptos issued by their governments. I think people overestimate the power that the governments have over us nowadays. In fact, it is much weaker than it was in 1950s, while many people think the opposite.
I think governments can force banks and other financial services to swap their current 'digital fiat' for tokens by simply upgrading their infrastructure, which means that people *probably* won't even notice a difference. In the end, people either use their phone to pay through an app or their NFC enabled debit card. People never had much financial freedom anyway, so they will not see it as a step backwards. If it works, it works.
I'm certain that when we're like 5 years away from now, people will ask themselves why they don't hear much about the blockchain anymore, and why banks haven't implemented it yet, while in reality it has already been implemented silently years ago alread. Think about it, the efficiency gains they book will be kept to themselves, and you still have to pay legacy fees to fill up their pockets.
