I don't know about that. Not the main campus, it's across one of two major bridges over the Allegheny, I guess some foot bridges as well - a lot of density and infrastructure in between.
The West Bank of the University of Minnesota was closer to the Metrodome than Heinz to Pitt's main campus. Minnesota's East Bank requires crossing the Miss, similar for Pitt students going to Heinz. Like Pitt, problem for Minny students was getting to the Metrodome via a practical walk - most students live on the East Bank. Regardless, students across the country aren't exactly going to games on time and often leaving early, this includes the SEC and other non-SEC campuses where student housing is quite close to the stadium.
NFL stadiums simply aren't a good match for CF minus a game here and there, every year or two - see Miami as well.