I know this is an old comment, but this is a topic I like to discuss.
Option A: Regulate the number of people entering the lower bowl and actually enforce it. They try this at every game, but it has been terribly enforced except for the Penn State and Wisconsin games in 2019. As others have said, there are for more students in the lower section than their are designated spots, so that is reflected in the upper deck.
Option B: Remove the upper deck of the student section entirely and expand the lower level to include two additional sections on either side, which I believe would be sections 113-135. These are all of the the bleacher sections around that endzone. This would of course bump some season ticket holders out, which is why I would not expect this to happen. However, the reason I would personally want this to happen is because there are very few P5 schools that have their student section split across multiple levels. It creates a disconnect within what should be the loudest part of the stadium. I think having a student section that wrapped around that entire endzone would create a much better atmosphere as a whole.