If Plutonium got a cease and desist, what if the project went open source before that happened?
While Plutonium would still be gone, others will be able to pop up in place of plutonium, and hopefully Activision will stop worrying about these clients.
It would be like the Club Penguin rewrites, when one is shut down by Disney, another one always reopens in its place.
Even if over the next few years Activision continues taking them down, there will be a time when they will stop and when that time comes, a client will be ready to take its place rather than spending months if not years reverse engineering all of these cod games.