See this is the problem - this idea and philosophy. Suppose a user happens to want to use a certain wallpaper? Why should that user be forced to use something very dark and neutral simply because the designers of the OS UI simply didn't want to provide mechanisms of ensuring clarity and adequate separation between figure and ground?
Every version of IOS to date has provided at least a shadow behind fonts and around important iconographic elements to allow them to be separated visually from their contexts. Mac OSX does it too. So does Android, and virtually every other operating system on the market. Why, then, is this sort of thing suddenly not necessary under the direction of Ive? Reducing the usability of the platform in order to further a primarily aesthetic venture is just a bad idea, and it should not have happened.