The more film we have, the more that other teams can use it. They are figuring out when/how to attack our defense. The flip side is that, as the season goes on, players start falling and becoming less than 100% for all teams. So, even a team with more knowledge about us can lack the bodies to do anything about it. But the same applies to us.
Then, throw in that these are college-age kids, rather than mature professionals, there is the randomness of games just slipping away and out of hand. Duke got blown out by Illinois and blew us out. We blew out Clemson (essentially) and got blown out. This is not as surprising as you think. Look at the results of most rivalry games. Talent and coaching cannot explain everything. The same Syracuse team that got shut out 19-0 by Rutgers (and had beaten then-lowly Northwestern 13-12 the weak before that), beat Nebraska the next week. And then did not make a bowl (in fairness, they were 6-5).
I just cannot believe that so many fans have such short memories to think that even a subpar QB cannot have a few above average games and get wins. Everything is either... .we are winning out and going to the playoffs... or we will not win another game. College football is almost always between those extremes. The Collins that played Duke--without getting substantially better or ever being a QB1 again--will win one more football game this year. If he improves more than that, we might win another. If he improves a lot, maybe we win 3 more games. But it's been one full game.