Well, they are based in several countries, so it would be harder to take them down.
I'm also not so sure they will be entirely necessary once the ship has sailed. Any trusted coders and code is fine. The freedom to audit it is all that is needed. Anyone can write the updates and upgrades. Getting to that stable network is the key. Once it's there we're free.
I do agree that like all things this project is most vulnerable at the earliest stages. If the uk govt swooped in before it had properly launched and gained some interest then perhaps it could be stopped.
Personally I think they have gotten far enough to make it inevitable now. So much groundwork has been done that any other keen and bright coder who chose to take on the challenge and finish the job will probably get there eventually. The paradigm shift seems inevitable.
I wouldn't worry anyway, the state is slow and stupid. By the time they start kicking up a fuss it will be far too late. It probably already is.
Besides, some people in the state will be smart enough to realise that they want and need robust security as much as we do. Control is just an illusion, but privacy and security have very tangible value to everyone at every level.