Unfortunately, that keeps us stuck in technological local maxima; the users necessarily operate in the framework of existing things and are thus unable to articulate novel things they actually want or need. These are simply things users do not think about in a sufficiently extensive capacity and manner.
That is fine for things that serve an obvious function. If you need a checkbox, use a checkbox, it doesn't need improving. If, on the other hand, you create a new type of control/interaction to solve a problem better, great. Also, what iOS did was not a single control but a completely coherent set of controls and interaction that might have lots of people working on it but which all had to pass muster with Steve Jobs before it was approved.
I haven't used iOS but have used MacOS and although I would argue that MacOS to me is not a good UI (you have to learn what most things do before you can do them), the consistency is somewhat comforting.
