In a generation with the likes of Red Dead 2, Zelda BOTW, Bloodborne, God of War, Persona 5, Mario Odyssey, and Uncharted 4 only one game reigns supreme.
I agree. Witcher 3 is among the best games of all time. The quality of the DLC goes a very long way to separate it from the crowd. The base game is extremely good, but then it gives you two more gigantic, excellent experiences in the DLC. No other game has ever done that, aside from MMOs.