He was commisioned to write whatever the devs wanted, they'd tell him they wanted some Pink Floyd or Jimi Hendrix and he'd program it for them. As fro IK being plagiarised, it bears a moderate similarity to that song posted to start off with, but yeah, Rob Hubbard's "version" is twice as long and changes tempo half way through - didn't hear any of that in that Sakamoto song... Inspiration is NOT plagiarism.