I was super excited about Fez because I loved the art style. But after twenty minutes of playing, I gave up, totally disoriented. I have a terrible sense of direction in general and that game was just me wandering around lost and miserable. :(
For me it was the first puzzle. The mechanics weren't clear and I had several glitches. The rest of the game was alright, but quite overhyped. I liked The Floor is Jelly a lot more, but it didn't get as much attention. Sometimes it pays to be a drama queen.
You can't reasonably make the claim that Fez became popular because Fish was a drama queen! It got excellent reviews and won many awards and contests. Personally, I think the attention was warranted.
I was probably not completely fair. But I really don't think Fez would've gotten the attention it got without Fish, and a bug ridden game like Fez makes me question the reviews. The gap between press reviews and user reviews on Metacritic seems to confirm my point.
Oh, and Fez, of course.