Yes and no...Banning from a bowl game doesn't seem like much but HS students considering USC will not take to that very favorably and thus it dampens the recruiting effort. and make no mistake, USC is a juggernaut when it comes to recruiting.
A second thought on “bowl banning”. Yes face time and prestige are important. A college coach once told me that the most important but hidden advantage in “bowl games” was the extra practice (two weeks?) the team got. The ability to coach, drill and work the students often carried over into the fall season where the results would hopefully show.