I think this is nice in theory, but it's naive. From a developer's point of view, an icon is an ad that causes you to click and read the description in the app store. I don't like it, but those are the facts.

The author argues that a movie app icon can be designed in two ways:

1. To stand out against other movie apps in the app store

2. To stand out against Mail and Safari on a device home screen.

The fact is, developers are incentivized to do #1 and incentivized against #2. It would be nice to live in a world where that was reversed, but as long as developers are competing for eyeballs in an app store against other apps in a search query that will simply not be the world in which we live.

I've run A/B testing on dozens of app icons. #1 becomes optimal as your app becomes more niche, #2 becomes more optimal as the niche becomes increasingly competitive. Compare and contrast the icons for "cinema" as for "sign language" to watch this battle play out. Cinema you get brand names, abstract art. Sign language you get a hand sign, or little kids (in the case of baby sign).