>shows that just 20% of PhD-granting institutions in the United States supplied 80% of tenure-track faculty members to institutions across the country between 2011 and 2020

I feel like this is not the best representation here as they sorta switched what they are measuring. Imagine if every single PhD from every single university became a tenured professor at the exact same rate. We'd still see a pretty big imbalance because presumably there are some universities which give out 300+ PhDs per year because they have a ton of programs/departments and others that give out 30+ per year because they have very limited grad programs.

Surely there is a skew but it just seems like a very deceptive way to look at it.

Would be like saying that 50% of all Americans who become teachers come from just 20% of the states - but not adjusting for the fact that 50% of the population lives in the top 10 largest states.