It seems there was a time when Apple UI designers consulted with experts in human psychology when designing their UI's to make them as warm and "human" as possible, emulating the interaction we have with the real world. It was more than just the skeuomorphism of implying a certain functionality by making an analogy between an icon and a common real world device - it was allowing the user to interact in a natural fashion in an interface which is an extension of the depth and texture of the natural world we as humans are most comfortable with. It was a place that was pleasant to be in, naturally increasing productivity and minimizing eye strain. The minimalist movement of late in user interface design abstracts interacting with our computers to the point of cognitive burden. Sure our brains can do the translation and figure out when a string of text is actually a button by context, but it's still an additional cognitive burden, and these all add up to cause subtle mental stress and fatigue. For example, it's actually less of a mental burden to understand the time displayed on an analog watch face than a digital one. That's because our minds don't have to form the mental image of how far into the current hour we are - it's already shown on the analog watch face. Determining how much time remains in the current hour requires even more mental processing with a digital display, but is still super easy with an analog clock. In addition to eye strain, another physiological issue from saturating our screens with white is that the blue component of the white can also cause insomnia if we use our computers close to bedtime. Studies have shown that blue light induces a waking state, while reddish-amber light prepares us for sleep. Our displays should at least favor a neutral color combination, inducing neither agitation nor sleepiness. The "white" light of our computer displays still can't come even remotely close to a white sheet of paper under natural light, so they simply shouldn't try. Starting with iOS 7 and Yosemite, Apple UI designers seem to have taken to minimalism like a religion, with no room for a middle ground or even a user option to bring back some of the beauty, depth, and usability of an operating system such as Snow Leopard. Aesthetics aside, it really is a usability issue for so many of us who find the light grey font atop a saturated white background in iOS 7, 8, and Yosemite to be unpleasant to use at best and simply unusable at worst. Our computers should complement our humanity, not run counter to our basic physiology and sensibilities. I guess the problem with building something like Snow Leopard is where do you go from optimal? How do you make something that's seen as new without it then being less than optimal? The answer is not to destroy what has worked so well for so long, but rather to build incrementally upon it with new features, while not changing the foundational UI guidelines set forth by Apple as it was under Steve Jobs. It's really that simple. I sincerely hope Apple will at least tone down the eye-searing white in a future release and return to what just worked so well for so many years.