When a school reports the percentage of students who submitted ACT in their CDS, it is exactly that. Same for SAT. If you look at the CDS for schools in any year in which they were not TO, you will often see that the totals exceed 100%. That makes srnse unless they limited the students to one test.
Either/or is the right concept for reporting what percentage of students submitted a test with their application. But if they require scores for all matriculants, they could have both.
I am curious about how many students have NO test scores at all. My sense is that most who do not submit do in fact have scores but feel they don’t enhance the application.