I totally agree. In the past, NCAA games were criticized for "Robo QB", which was the perception that unless you sacked the QB, he would get a rid of the ball and complete unrealistically high % of passes to open receivers that they would always seem to locate, even under pressure.
I don't think the problem is that the QB's are perfect - the QB's do miss passes and make mistakes. (There's also some bizarre glitches where the QB drops back and throws it away before he could possibly have even read the defense). I think the Zone A.I. is just so bad that there are clear exploits for the passing A.I. to take advantage of.
Madden and NCAA producers have said for years that the proper way to play the game is not to "switch and dive" over and over again. But if your A.I. teammates have no awareness of ball carriers running right past them, it's only natural that you'll try to take control of them and fix what they aren't doing.
The fundamental problem with video game defense is that you only control 1/11th of the action, but they need to give your input an unrealistically high proportion of impact on the outcome of the play. The way they do that on higher levels, is to make your A.I. teammates increasingly dumb, so that you have to take control of the action. Otherwise, you could just play as a DT and run into the block everytime, and it'd be as if the computer was controlling the whole defense.