2. Better opportunity to win a conference title
The opportunity for Brohm and Louisville to win the ACC is right now. After defeating Miami, the Cardinals have gotten their toughest ACC opponent out of the way and even claimed a win in the process. Louisville is 2-1 in ACC play and doesn't face another currently ranked opponent for the rest of the season.
With how the rest of the season is laid out, there is a real possibility that Brohm leads the Cardinals to their second ACC title appearance in three years. With the legacy Brohm has previously established at Louisville and the one he continues to build, the Cardinals could remain atop the ACC for years to come.
On the other hand, if Brohm were to leave for either Penn State or Florida, the chances of him winning a conference title would decrease significantly. Penn State is currently 0-4 in the Big Ten, and in a conference that includes Oregon, Ohio State, and Indiana, it would not be easy to turn things around. The challenge appears in Florida, with them being in the SEC. The Gators are 2-2 in their conference and have a gauntlet of a schedule, having played four ranked opponents and are slated to play three more.