They can't control cryptocurrencies but they can certainly create their own and ride the wave of interest cryptos have gathered over time. Seeing that people still drool over cryptocurrencies and how easily people can be swayed with only the term, they're willing to jump on-board and keep up with the decentralized cryptocurrencies in order to gain control towards people's spending. State-issued cryptocurrencies really aren't appealing, since it's like fiat but with more control over what you do and more eyes on what you use it to. It's very disturbing to know that every step of the way, someone sees what you do and what you use your money at, and to know that it's easily achievable through state-issued cryptos, it just becomes scarier.