The only time it's dumb to go for two is if there's a penalty or something that pushes you back. Any NFL offense should be able to get that frequently enough to make the numbers in favor of the 2pt attempts. People sometimes think of that decision as only affecting the offense, like thinking the downside of having to score twice is really huge. In reality, the numbers should and do take into account that the opponent will have a chance to score. Missing the conversion meant it didn't really matter if the Ravens scored or not. So there wasn't that much to lose.