There are things that are pretty unlikely to offend, things that are very likely to offend a lot of people, and things that are very likely to offend a few people (this kind of humor is often called "punching down" when the few are a low-power group and "punching up" when it's a high-power group).
Nobody is calling for zero offense; that's a slippery-slope argument that doesn't really apply to the situation. And nobody has silenced PewDiePie; he's completely free to continue to publish his content on YouTube (with proper community flagging, within the guidelines of the YouTube community, and even if he were no longer free to do so, he wouldn't be "silenced;" he'd just have to move his content to .mp4s hosted out of his own pocket).
What has happened is YouTube and Disney have both exercised their option to no longer pay the guy for being offensive, which they are perfectly within their rights to do.
In terms of the more general "Just wondering aloud" question: The old Streisand Effect is still in play, but the Internet is now a mature enough platform that it has "these sites" and "those sites." You can find all manner of things completely unacceptable to YouTube's community standards linked off of 4chan. Keeping them off of YouTube does probably make them a little harder for most web users to find (since YouTube's search, indexing, and relational systems are so convenient). That's likely working as intended.