Earlier quoted context omitted.
If you read the article, he's not making that assertion about the relative worth of Android. (And opening up with that as the basis of your argument is a disingenuous tactic, if done intentionally.) He's arguing that the third-party software library is weak, especially away from "enhancement/tweak" type software. Flexibility is useful only insofar as it translates into capabilities of high value to end users. It's no…
The point you make about the killer app is very true. Halo on the XBox came to mind. I think Google hoped turn-by-turn navigation would be it initially for Android, but I agree that (for the average user) there aren't any killer apps. If you get into domain niches (such as medical), that might be different.
Today I've only really seen four killer apps on a phone... email, SMS, mobile web browsers, and GPS. Facebook would be a marginal fifth. Everything else is stuff that frankly most people would barely notice if it was missing.