If that is true it might have only been for the Eagles and Phillies, or with exceptions for special events (which playoffs and FIFA both would be). There are often events at both the arena and one stadium, and Temple football only brings an arena-sized crowd. But in this case it won't be simultaneous (no way Phillies are going to play at 1, and probably not 4 either).
There was definitely baseball, soccer and a concert one time this season, I remember the transit and parking advisories.
My first time at CBP in 2004 was before an April Flyers playoff game. Nothing at stadium tho.
Ah here's the other one I remember, no arena event, but big training camp crowd for Eagles opposite Chris Brown. Parking overlap, but the gates for concert opened after the football event was over.
https://www.mlb.com/press-release/press-release-travel-advisory-multiple-events-in-sports-complex-sunday-aug-10-2025