A government can legislate that developing "cryptocurrencies" enables money laundering, terrorism and whatnot, and suddenly any developer is under threat ot being arrested if they are not anonymous. Of course any developed democracy would need to go through various proceedings to get such a thing done, but it's not impossible, and it's definitely possible in totalitarian regimes like Russia, China and whatnot (not to mention North Korea, where I sometimes cannot even fathom this nightmare state actually exists)
In fact, if we look back at the reasons, we still return to the classic reasons, which are only intended to make it seem like such a thing exists, but in fact, the reasons for money laundering or whatever is negative in crypto are exaggerated and if we look at it, there are actually more cases that are worse than that and the government actually knows that saying negative things like money laundering, terrorism or whatever it is doesn't have much real impact.
On the other hand talking about China which is still very vocal in saying they will not accept Crypto but on the other hand there are currently some news about Hong Kong which does have a goal of becoming a crypto center and China supports them in this case isn't this a comedy.
Hong Kong's Crypto Hub Ambitions Win Quiet Backing From Beijing
SourceThis means that in this case the government only prohibits and punishes miners only as an alibi to smooth out the plans they make, even though we really don't know whether the conditions are correct or not, however, sooner or later such things may actually happen because they are indeed monopolizing the conditions of the government, it is clear that they is the champion.