They can forbid it if they want, the problem is how are they going to enforce this? I mean more than a decade has passed since satoshi released the first cryptocurrency and to this date there is no reliable information that says that they had been able to track him down since he took all the precautions that he could so he could remain anonymous.
What is stopping developers in the future to do exactly the same and do the best that they can to protect their identities and release their coins anyway? To me regulation seems like the best path for the governments, otherwise they are going to make a fool of themselves.
That's an excellent question. Governments can forbid developers from creating a new coin, but it'll be hard to prosecute those which are careful of leaving any tracks that would link them back to their identities. Someone like Satoshi would be hard (if not impossible) to find in order to enforce the rule of law. The only option would be closing centralized exchanges altogether. But even so, people are able to gain access to crypto/Blockchain tech via other means. Decentralized & P2P exchanges, atomic swaps, and the TOR network make it all possible for people to avoid government restrictions in the first place. Mainstream governments will have no choice but to "live" with crypto or get left behind in the dust. We'll see how everything will turn out to be the more crypto/Blockchain tech becomes popular worldwide. Just my opinion
