But there's so much money in academia. Where's it going?

Universities charge stupid amounts (50%+) of overhead to researchers. The PIs basically run a lab, hustle for the funding writing grant proposals, and uni takes a big fat cut of whatever funding gets pulled in. And that overhead all gets spent on useless administration, buildings and facilities, investments, and basically anything other than the research the grant was for.

https://academia.stackexchange.com/questions/25910/what-does...

The problem is that there's so little money in academia. In the US, state support for public universities has plummeted in the 21st century. In the last state I lived in, the state university near me went from providing over 75% of teaching costs to under 25% in less than 20 years. Tuitions have risen, but it's important to understand the sticker prices are usually discounted with financial aid. If a university raises tuitions by an amount x, they are usually brining in less than 1/2 x new funding. Ironically, reducing university funding leads universities hire more administrators, as they attempt to replace lost funding with donations or indirect costs.