Government’s can crackdown on a specific project as like they can block IP's or URL's in a project, but there also solution if you will use VPN. They can shutdown for a individual project and it’s happened in many counties but they can't totally stopped crypto. And governments will never crackdown specially decentralised project, they can only controlled centralized project if they want.
The crackdown of crypto is very possible in the system. Crypto projects are best and good for improvement. The Government means good for the country, they're trying their possible best to eliminates cryptocurrency because they sensed it to be threats. Government have power and dominates every activities within a country, they mean good and development for a country, one of the major reasons they're not sliding back but focused on their budgets. The government have a hand in the restrictions of crypto projects in the market.
The government can do many things if they wants in their countries, as like blocking or strict restrictions in crypto, that happen in my country but i see crypto is going more popular day by day, because if they shut down a site, people resort to alternative methods as like using VPN or other ways. So government can dominate but can't totally stopped it.