That's like saying that Apple should've used air gestures, or a round shape or a more futuristic UI with the first iPhone. Instead, they just copied existing icon grids, touchscreen pinch zoom and flick scrolling, and a bar shape with basic smartphone functionality.
Everybody adds on to what comes before, and/or what has become popular (like larger screens for phones and smaller screens for tablets, or notification shades, or flat UI design).
As for Samsung inspiration and innovation, they just showed off the world's first 5.7" foldable smartphone screen (with touch) at the recent CES, reportedly using new materials to solve previous problems with broken traces.