If your game reeks of artsy fartsiness for no particular reason that's a pretty good indicator it's pretentious. Limbo is a perfect example. No dialog or words at all. The color palette is on a slider of black to white and every shade of grey in between. You play as a child in a dark and hostile world. Did it have a message? Did it have a point? I can't think of one.
So you've created this tone and art style... why then? It doesn't serve any purpose and there's not really a point to it. It dangles the prospect of depth in front of you the whole time and then it doesn't pay off by the time its over. That's how I would define a pretentious game.
At the end of the game, you do something which sends you back to the exact same place and scenario of the game. Being as the game is called "Limbo" I thought "oh cool, so it's a loop. That's pretty clever" but then a girl shows up, implying that's who you were looking for and you won the game.