LOL No it not JFK Reloaded, admittedly, though that game, in itself did not attempt to get inside the mind of the shooter, not encourage you to kill as many people as possible, it was simply a cold physics simulation for the main part.
The graphics are indeed, along the lines of SNES Zelda games (though it also includes photos and CCTV footage from the actual incident), but I think the subject matter and the way the game was approached has offended a lot of people who were directly involved or affected by Columbine.
Yes, this tragedy needs to be addressed one day, but I don't think this game does so with equal empathy for all the families involved.