> Also true of undergrad at so-called elite universities in the U.S. The "top schools" have something like 95% matriculation rates.

I think you mean "graduation rates", but I completely agree.

That said, there are some majors at elite schools that are very tough. The catch is that the enrollment in these majors/programs decreases rapidly as the weaker students change majors to something that is easier and/or requires less work.

^ this! Though I would argue not all top schools make it easy to change majors also the in major matriculation rate (people who start and dont transfer/change majors) vs school matriculation rate (do they graduate) is very important especially with the current focus on mental health at many universities.