Along with the copyright black hole, which will make the 20th century appear to future civilization as a second dark age of art and thought, is the fact that any digital media stored in obsolete formats disappears from the world.

Even if we keep copying the bits from one storage medium to the next, eventually we lose the programs that made those bits meaningful. Consider the challenge, even 50 years from now, of finding a complete copy of every binary file in the world today. With no idea what files are cad, which ones are images, which ones are word-processing documents, how do you reverse-engineer the file formats?