The interesting thing to me is is that each of these inflection points, the industry had a set of 2-3 possible "next big things", and then none of them happened and the actual next big thing was something different.

In the early 90s, the next big thing was WebTV, VR, or PDAs. Instead, we got the WWW.

Post dot-com crash, the next big thing was P2P, enterprise software, and the semantic web. Instead, we got social networking.

In 2008, the next big thing was casual games, (micro)blogs, and embeddable widgets. Instead we got mobile and the sharing economy.

Now, the next big thing is wearables, IoT, or AI. And who knows what we're going to get?

Looking at the patterns, it looks like the mistake most people make is to extrapolate the last big thing into the next, not being willing to make a big enough conceptual jump. So enterprise software, the semantic web, and P2P are all offshoots of the WWW and all enjoyed some modest success, but a different offshoot of the WWW (social) connected it to a different area of peoples' lives. Casual games, microblogs, and embeddable widgets are all offshoots of social, but a different offshoot of these social changes was enabled by mobile, which enabled totally different ways of interacting.