For me, what ultimately gives the original Xbox the win is it had killer exclusives, something the Xbone lacked.
I mean, Halo 1 and 2 speak for themselves as all time classics, but then there was Panzer Dragoon Orta, Project Gotham Racing 1/2, PC games you couldn't get on PS2 or Gamecube like Doom 3, Morrowind, and Half Life 2...