Let's just say the unlikely happens
And Hollywood and the music guys manage to sue the users and organizers of online file sharing out of business. Let's imagine that against all odds, you can't find copyrighted stuff online any more.
If that happens, sites like ibiblio - Sights and Sounds begin to do better and better. Here's hours and hours of stuff for free.
Now what you end up with paid online radio and free online radio. Paid online video and free online video.
At first, the paid stuff is good and the free stuff is less good.
But soon, producers seeking an audience start to make their stuff free. Because when they do, the audience goes up 100x.
And then, in order to compete, others do the same thing. Wouldn't you if you had a touring band? Wouldn't you if you had already exhausted your DVD sales and wanted a big enough audience for your sequel?
And then, of course, we end up where we sort of are today.