It's entirely anecdotal, but in my experience in academia (which consisted of 4 years of post-master's PhD), I've seen this happen exactly 0 times.
For the most part, it’s just another artificial rung the system uses to justify exploiting people.
The administrative organization continues to expand, and it must be paid for somehow.
That also used to be much less common back in the day.
2003: 2294 Arts & Sciences PhD students and 3500 administrators + managers
2021: 2895 Arts & Sciences PhD students and >5000 administrators + managers
So administrative growth seems to have outpaced PhD student growth by some margin over that time period.
Regardless, the secret to high research productivity (per dollar) at universities is cheap labor from grad students and postdocs.
Sources:
https://oir.yale.edu/data-browser/student-data/enrollments/g...
https://yaledailynews.com/blog/2021/11/10/reluctance-on-the-...
According to the census, from 2000-2018, the percentage of the population holding PhDs doubled: https://www.census.gov/library/stories/2019/02/number-of-peo...
So Yale's PhD count grew a bit, but nowhere near as much as the rest of the country's.
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But mostly, PhDs used to be way rarer in the back in the 50s (along with college degrees in general). If you look at Figure 1 in this NSF report (https://ncses.nsf.gov/pubs/nsf25300/figure/1#), it shows the number of PhDs tripling in just 15 years from 1958 to 1973. After 1973 it slows down to merely doubling over the next 50 years.
Admin growth might be a factor, although I'd want to look at national data first. Your own article says "... Yale had the highest manager-to-student ratio of any Ivy League university, and the fifth highest in the nation among four-year private colleges" so maybe it's an outlier.
50 years later, the Molecular Biology postdocs were not so lucky. Not even an honorarium. "Maybe in a few years..."
We can always argue about whether it was worthwhile ofc. Moneywise, definitely not (though the pay wasn't all that bad compared to industry compensation in my countries). But I learned what I wanted to learn, and the issues the position had were speficic to the place, not the concept of the position, if that makes sense.