I agree with the general thrust of the article that Apple might be trying to do too much at once, and changing things for sake of change.
People though seem to be forgetting just how massive a change iOS 8 is under-the-hood. It might not look like much because the UI changes are minor compared to iOS 7, but introducing extensions, 4,000 new APIs, continuity features, and a new programming language is not a minor undertaking.
iOS 7 was the big user-facing change, while iOS 8 is the big developer-facing change. The 64-bit transition was the big under-the-hood change with iOS 7, and 64-bit devices indeed crashed twice as often. On my 5s, iOS 8 is much more stable than iOS 7 was upon release. In terms of stability and performance, it's now easily on par with 7.1.2. But, iOS 8 also seems to have more headscratching changes and random bugs (e.g., the reported Bluetooth and wi-fi issues).
Might not be possible given how quickly the mobile market is evolving, but Apple might need to do the equivalent of a Snow Leopard update (i.e., "zero new features"), and take a step back in order to focus on tightening up the OS so that it runs faster and more reliably. They've already done a lot of heavy lifting with the 64-bit transition and adding a long list of new features and capabilities.
With OS X, Apple did not follow any fixed schedule for a long time. That allowed the software to bake until it was at a certain level of readiness. Putting both OS X and iOS on parallel annual cycles is a precarious high wire act, and buggy releases might be the not-so-surprising outcome of letting external demands dictate the schedule.