Yup. I like Apple, but even I consider "perfectly timed" to be a case of revisionist history.
The rest of the summary falls apart under scrutiny too. Microsoft can do the Surface Pro 3 because it has a common OS across both platforms. Apple does not. In fact, despite some recent iOS-ification of OS X moves, Apple has always publicly stated that they think the two should remain separate, and with Yosemite they've made it ABUNDANTLY clear to anyone paying attention that they really do view them as two separate classes of devices intended for two entirely different sets of tasks and that each class should have an OS that fits it. Yosemite is one giant, "Now that we've finally decided we're not turning OS X into iOS, we need to give OS X users more control and then make the two OSes work well with each other" step.
In looking through the features that it shares with iOS (e.g. iCloud, Extensions, flat UI appearance, etc.), the one trend I keep seeing repeated is that Yosemite was allowed to diverge from iOS in a number of ways that make it more powerful (e.g. able to directly manipulate files in iCloud Drive, more varied types of Extensions allowed, more ability to customize the UI's appearance now than anytime in recent history), rather than being constrained to only do as much as iOS, which had been the somewhat worrying trend of the last few years. And then they've added methods for helping the two OSes to hand off work between each other or pass files back and forth more easily, allowing users to work on whichever system they feel best fits the task they're working on.
If Apple wanted to unify their devices on one OS in the very near future, Yosemite is pretty much the exact opposite of the OS you'd release.