If the digital currency will be held by the government it will become a centralised. Which is more secured and legitimate. It may be a good idea in terms of investment, savings and payment.
It can happen in countries with the worst economy. The huge inflation can make the government take a decision to start creating their virtual currency and save the country and its people from poverty.
No they will take charge as demonetisation to solve that issue. If any government have the idea to create the digital cryptocurrencies will be good for them to sustain in this competitive world in future years. There is no pic possible days to sea digital currencies from government.