I had to look this up. Honestly, it appears app icons are flattened and redesigned, and the 3D glass dock is removed, but otherwise pretty much what Apple were doing to OS X/macOS around the time of El Capitan/Sierra, right?
Also, I think Ive mostly was tasked with the industrial design of Apple hardware — not so much the skeuromorphic elements of earlier iOS or older OS X, or the flattened, post-Aqua/Marble UI of OS X and, later, the post-Yosemite flatness of macOS. While I’m sure he was invited to chime in as one of the folks in meetings, I doubt he was central to the UI/UX core team behind those design decisions. Of course, I’m only guessing.