Apple started off as a champion for usability and user-friendliness and that is the reason why I liked the mac so much and stuck with it through all these years. You can see it in such a subtle way as how the menu-animations are handled. Click on a menu and it is instantly there, no animations at all - but when it goes away there is a little fade-out creating a richer experience. The fade-out does not take up your time or interfere with anything, but a fade-in would (so no fade-in).
More recent additions to the iPhone and the mac seems to "forget" about this principle. Animations and appearances are more important than usability. In iOS 8 this philosophy, that watching animations is more important than usage, had its peak. Despite how much faster those phones were, they seemed sluggish since you always had to watch animations end before performing any actions. Here is a video comparing the original iPhone (which had a deep focus on usability) with a newer running iOS 8 to drive that point home: iOS 3 vs iOS 8. Many of these problems still exist in iOS 9, but there are improvements.
One example how things have started to improve is how the calendar app handles new entries. On OS X there is a button with an inbox symbol and a number of new entries (if you have no new events, this button is hidden). Clicking the inbox button populates a list with entries and an "OK" button, which makes the entry go away. However, if there are many, each click triggers a little fade-animation where you just have to wait. The same list on the iPhone however, does not require waiting for the animation to finish. This is just one example, and OS X is riddled with these annoyances and iOS has a bunch of them too.
That makes it seem like there is an internal battle at Apple for and against usability. It could also be the case that Apple has lost its vision and don't know what it's good for anymore or it could be due to unrealistic deadlines or "marketing driven development" where the engineers simply don't have the time to build great software, as talked about in the famous functional high ground post.
The solution is of course to write better software, but since Apple is incapable (no matter what the reason behind is, facts are facts - they are just not capable anymore), there should be a setting to disable all animations in order to at least mitigate some of the most apparent usability bugs. Then Apple could also see how many of their users that feel so plagued that they must resort to killing all animations altogether (if it's feedback they need to decide if usability is a good thing). Like how this plugin to Mail has saved my mac from kernel-panics every other time an animation plays, yes the animations are not only bad for usability but can also crash your computer (and yes, my older 2010 MacBook Pro running Yosemite kernel panics ~50% of the time Mail.app calls core animation to play animations for me).
The upside of this story is that we who develop and/or design software can learn a great deal. Apple probably uses a lot of "bells and whistles" because it works - it sells software. You should never ignore animations, but to keep your loyal customers happy, bells and whistles should never get in the way of usability. Perhaps a fine line for some people but for me, a single developer, this usually means that animations need to come in last - after functional requirements and features are met, and by that time I'm usually over deadline and the animations simply get cut.
I guess I just wish Apple cared more about their current users than making UI-demos for their new ones.