That's why it's a metaphor, not a strict skeumorphism. The core ideas taken from the concept of "paper" are stacking, layering, print-design-style blocks of co

That's why it's a metaphor, not a strict skeumorphism. The core ideas taken from the concept of "paper" are stacking, layering, print-design-style blocks of color, and the idea that things can be shuffled and moved but cannot instantly appear and disappear in/out of thin air. That doesn't mean it's literally trying to be a pile of looseleaf, just that it's mimicking those abstract concepts from the real world in an attempt to make the interface intuitive and less "magical" (in the negative sense).