Interestingly, according to the report in your link, UPenn pays over 3 billion dollars in salaries, but it has around 1,400 faculty for ~10,000 students. This means that either the instructors are fabulously well paid, or that the vast majority of money is going somewhere else. And indeed according to [0] just 4.64% of salaries are paid to instructional staff, with 23.9% or 2078 of paid employees being management staff. So if I am reading this correctly, they have far more administrators than actual academics, which is rather incredible. Incidentally, according to the same link the median percentage of salaries paid to instructional staff is 30% for similar doctoral universities.

[0] https://datausa.io/profile/university/university-of-pennsylv...