It's well known that authoritarian countries aren't crypto-friendly.
That's not always the case though, Belarus for example is very crypto-friendly and it's a dictatorship...
While some democratic countries can be completely against crypto.
In the case of Iran, I guess they have to do something to prevent their national currency to drop even more.
Not sure if they're already in the hyper-inflation stage, but things aren't going too well with their currency.