Well the fact that they've hammered on them for years doesn't mean they're not trivial, it just means they've spent a lot of time on them. And I think we've got to differentiate between the app being [non-]trivial and the infrastructure behind it supporting the massive load being [non-]trivial.

Uber and Airbnb are most definitely not trivial. Anybody who has ever worked on a remotely complex two sided marketplace project can tell you that. The UI/UX alone is incredibly hard yo nail down. The fact that they made you think that they're trivial really shows that they are doing a lot of things right.

Trivial applications require tens of thousands of man hours. Actually, a lot more to make it scale. By trivial I don't mean "it doesn't require a lot of work". Any application requires a lot of work. By "trivial" I meant that they're not creating anything significantly new technology wise, and the value they create is mostly by making existing work/services easier to use and provide.