I can’t answer that question because I’m not an AO. But I have not heard an AO say a one-and-done is weighted more heavily…but that could probably happen at least sub-consciously…but most AOs have no visibility as to how many times an applicant took the tests.
For example, for schools that allow self-reporting, they don’t know how many times an applicant has taken the test. The applicant reports their highest composite and subsection scores, and the date(s) of each. If an applicant’s highest composite and subsection scores were all from the same test…that still doesn’t necessarily mean they only took the test once, so how would an AO even know the applicant was a one-and-done?
The only schools that would ever have visibility to that are the ones that require all scores to be officially submitted. There’s just a few of those left.