Academia is a pyramid, for every PhD position, there are fewer post-doc positions, far fewer permanent staff positions, and even fewer professorships.

For most people, an academic career is a dead end. So, reduce the number of PhD and post-doc positions and increase the wages.

Universities have been doing the opposite. E.g. some Dutch universities stopped offering relatively well-compensated employee PhD positions and replaced them by bursary positions with far lower compensations. The primary motivation was that they could hire more PhDs for the same money. That maybe works when there is a recession, but when there is an ample supply of jobs, many good candidates will just choose an industry position instead.

Besides that, universities have gained a lot of administrative staff over the past decades. Plus some universities spend hundreds of millions of Euros on fancy buildings. Sure, it looks nice in PR material, but they could've also built something functional and use the remaining money for better salaries.