Don't misconstrue what is being said. Imagine the sign saying "Please paint my car but we reserve the rights to remove anything we want". That's essentially what the YouTube user license says.

Graffiti is done without permission. What exactly am I misconstruing? That's exactly why the analogy is so bad.

Many user-licenses forbid things like spreading "hateful" (I actually don't like that word) content. Some users post such content, thereby doing something which they had no permission for. When that content is removed, in compliance with the agreement, they call that censorship.

So my analogy still works.

The difference is that on YouTube some "graffiti" are permitted while others aren't whereas on my car, none are permitted.