True, but each individual school is big enough to have actual data associated with it. Conclusions about the system as a whole might not work, but you can make a reasonable guess about whether you want to send your kids to a specific school.

Individual schools but we already know different schools vary greatly. As a form of selection bias, I bought my home in an area with schools where most kids go to college. The house was more expensive, so also needed to be richer, and it’s a two parent home, my neighbors are the same. It is t necessarily the school that’s good, it’s just selection bias all the way down.