Unsure why you were downvoted - Apple has borrowed heavily from Dieter Rams in the past decade or so. Heck, the current iPad Music app is a straight lift from the famous Braun SK radio/record players.

That being said, there's no real reason why Apple has to use textures anywhere. Dieter Rams designed physical products which by their nature must have some texture or another. Having texture is purely optional in a digital product.