During the pandemic, many universities in the United States have suspended the requirement of SAT, ACT, or equivalent tests. I work in one of them. It seems that some universities have removed such requirements permanently. My personal experience is that the removal of the test scores has very noticeable effects.
I wonder if there are measurable effects across the country. Moreover, what is replacing test scores? Obviously Caltech cannot accept 100% applicants, so what is the filtering mechanism now?