I could in 2 minutes deploy a new smart contract for a coin that allows for the owner to mint money whenever they want. Cryptocurrency doesn't stop a coin like that from existing.
Many central banks and governments are experimenting with cryptocurrency/blockchain. I believe some have gone live with various projects around voting, currency-issuing and accounting.
Notably also, the US government is using USD-pegged crypto currency "USDC" to circumvent governmental corruption in Venezuela, in order to deliver economic aid directly (to intended recipients who weren't receiving it through government-controlled Venezuelan banks):
