Indeed nothing lasts forever but I do not think that Bitcoin will be ending anytime soon. If the beginning of government's interest to create, navigate and circulate a centralized digital currency would be the end of Bitcoin, I don't think that it is happening soon. Every nation has a different government system, capacity to fund resources and technological advancements. On the contrary, the government of some countries has been very open with cyrptocurrencies that they tolerated different establishments to engage with transactions using Bitcoin. Also, I think that even if the government would start circulating their own digital currency to compete with Bitcoin, they would still choose the latter because of its features that they were enticed with foremost as to why they engage with cryptocurrencies.
The easiest way would be to issue an official centralized stablecoin of the State, where each person could have access to it. Like with current cryptos, besides having the wallet address you will have two IDs - one for your eg. transaction title (like invoice no 324/03/09/20) and your social insurance number. Most likely, this would be a solution coming from banks, as you will be able to open these wallets only at banks as a part of a bank account. Why banks? With people abandoning bank accounts, one of the main sources of their income will slowly start to disappear. In such a case, other fees would need to increase or whole banking system may be on the edge of collapse.