One can imagine college administrators using this to justify tuition hikes:
Not only do cheaper universities lead to lower average incomes over time, but students who attend low-return schools may find it more difficult to repay their student loans.
Some of this can also be due to geography. A decade ago I looked at the average starting salaries of new MBA graduates and, not surprisingly, those working in NYC finance earned a lot more than those graduating and working at a manufacturing company in the midwest, and that in turn, was a lot less than those working in high tech in Silicon Valley, Seattle, Austin, etc.
Of interest, average MBA starting pay was USD $110,000, just before the pandemic hit. Today, some top schools say they are seeing starting salaries of $140,000 or more, and Duke University says some grads received $175,000 offers with new hire and annual performance bonuses added to that. Note: Those receiving these offers likely have many years of work experience prior to earning their MBA, and some may also have other specialized education (such as grad degrees in engineering or medicine).
Over much of the past 20 years, there were regular annual predictions that the MBA degree was no longer valuable, and its usefulness was past its heyday. Hah hah. Like so many expert predictions, that one too seems to have failed.