You know China, they produce everything cheaper. So, I think it is about efficiency because money printing is not like a newspaper printing. Money need a security features so it need a special technology too which is expensive.
Adopting cryptos is not that easy, not everybody have access to internet or even know how to use computer or smartphone. Not now, maybe 20 years from now.
I agree with you, adopting crypto into state finance is still a difficult thing to do at this time. other than that crypto prices are also unstable, this is a very important thing that must be considered before the state changes their finances using crypto.