They will never cancel it because 75% of the people watching the SB are either casual fans or not football fans at all but the halftime show needs to go. To have the 2 best teams in the world playing for a half and then they have to sit around for 45 minutes instead of 12 during the biggest game of their lives is stupid. That is too abnormal compared to what the game normally is.
Music is way more fragmented now so no more than 20% of the audience is a fan of the act regardless of who it is anyway. Just do it before the game or something if you must do it.