I'd just say don't hold your breath until you find a perfect anything. Security is only an illusion, as is banning and filtering, and it's honestly better that way. If censorship tools were perfect, we would never hear from people in countries with oppressive regimes about what's going on in there, we'd never hear from whistleblowers about war crimes committed, etc.
Would you really want such a filtering power to exist anyway? Who would control it? Would it just be "another rule" that governs its use and its targets? Who controls that rule? Is it somebody you trust? Who would get the power after that person dies or is corrupted? How would you spread the knowledge of his corruption? It'd be impossible.
See what I mean? There's just no perfect answer, and there never will be. Freedom will always be dangerous and have huge negatives, just as surely as death comes to everything that lives.
Life is riddled with paradox, it's just our choice which side of things we look at.