If you have safety, discoverability, and direct manipulation you have less of a need to turn a small flat piece of glass into a simulation of a physical control

If you have safety, discoverability, and direct manipulation you have less of a need to turn a small flat piece of glass into a simulation of a physical control panel. Mobile device screens are a new medium. Do the things that free you from pre-smartphone thinking. "Flat" isn't a goal. Neither is realism. You can't wireframe direct manipulation (or even long-press, or multi-finger touch). So it is underutilized.