Even though there is a lot of (social) legal sharing going on between users, the focus is always on illegal sharing. He has a point there, though I think it's a pity.
IMO it's not even that suited to piracy, as the deduplication means that they can find everyone that has a file! Torrents are way better for that.
The principles of dropship could be used for sharing photos, videos, public datasets, git-like source control, or even as building block for wiki-like distributed databases. The possibilities are endless when every file can be called up with just its hash.