That's a hard question because it involves the laws of several different countries. There probably isn't a single answer. Part of it likely relates to indirect

That's a hard question because it involves the laws of several different countries. There probably isn't a single answer. Part of it likely relates to indirection. Hosting illegal content, vs linking to illegal content, vs redirecting to a site that links to illegal content are all increasing levels of indirection. A country may wish to take down illegally hosted content, but not want to take down indirect links.