That's not true. The problem is, for any given file online, I may have permission from the owner to access it, but you may not. I shouldn't be prohibited from a

That's not true. The problem is, for any given file online, I may have permission from the owner to access it, but you may not. I shouldn't be prohibited from accessing it just because you don't have access, so the central service needs to know who is accessing it and know their rights to said file. Without that, there is no way to tell if a link is really legal or not. And that is what Google was saying is impossible to handle.