The math behind the material value is simple, when reproduction costs are low, the originals are losing their values very quickly. LPs have hold their values for decades, because it was extremely hard for regular person to make a copy. But once we moved towards cassettes, CDs, MP3s, the value of original media was decreasing drastically.

Any kind of material which can be scaled and reproduced quickly have very short shelf life, this is not just case with music and movies, but also with clothes, furniture etc.

Apps are also losing their values because software reproduction is getting more efficient every day, so to stay on the top in the market such AppStore, you have to literally reinvent yourself every 6 months, which is really hard, and reason why so many apps fail. It’s not that easy to keep your creativity on such high level for long period of time. Not to mention the costs involved to materialize that creativity.