I don't think it's possible, though. Or at least, I think it's harder now than ever before. The internet isn't completely decentralised, but it's at least spread out enough that it's seriously difficult to shut down any one part of it, at least without being willing to take some serious authoritarian measures. Look at how difficult it's been for the most influential media companies in the world to fight piracy, for example.

I genuinely think our society is one of the most censorship-resistant societies in history. This comes with its own problems (how do you deal with media that genuinely is harmful, like calls to violence or plots to abuse children?) but I think this is the tradeoff that one has to make when dealing with censorship and liberty. The more you make it difficult for the authorities to shut down good speech, the more difficult it becomes to protect against harmful speech.