I think this is a centralized ecosystem "brainworm." Every feed publisher would be responsible for providing a feed that does not include illegal content. This

I think this is a centralized ecosystem "brainworm." Every feed publisher would be responsible for providing a feed that does not include illegal content. This is just a protocol for cataloging and distributed information about content. So, it'd be like asking "how does TCP/IP" handle illegal content? It doesn't and that's not the purpose. Now, publishers of feeds could indeed keep illegal content from being linked(in a naive way) by pairing this protocol with another protocol that can check hashes of file content against a database of copyrighted works signatures. If copyright holders want to protect their works online they should be making it easy, by providing such a service.