It's a different problem. With the general Internet, when illegal content springs up it can generally be dealt with (speed & mechanisms dependent on the type of content), and the rest of the Internet chugs along just fine. Systems that try to combat that (tor etc) do so with sophisticated techniques, and it's a cat & mouse game against the authorities.

Fact is, we are hosting a blockchain that allows arbitrary data to be stored in it, with no mechanism to remove it, and hoping that people won't take advantage of that in a way that harms us. Is that wise?