Braid has some good puzzles, but aside from the "plot twist" of the final level, its "art" aspect is pretentious and overwrought. Shadow of the Colossus was a good recommendation, though I'd pick ICO. Really, though, if he doesn't want to play a game, I don't see why he should have to. Just bow out of the conversation and leave it at that -- which is what he's just done.
In addition to the narrative and the "twist", Braid is also viscerally beautiful, with the music and visuals creating an emotional experience that makes it hard to deny the label of "art". It's also highly approachable for someone who doesn't play many games, though a casual gamer is not likely to make it through to the end.
> Really, though, if he doesn't want to play a game, I don't see why he should have to.
Oh, I agree. He didn't fully backpedal, though; just state that "maybe someday" a video game would come along to prove him wrong. Even if he admits that his opinion has no relevance, he still clearly holds the same opinion about the current state of games.
(And admittedly, none of this actually matters. It's just good old-fashioned "Somebody is wrong on the internet!" :P)