The AO changed their policy recently. They explicitly disclosed this for the 2020-2021 cycle:
During the 2020-2021 admissions cycle, all interviews will be conducted virtually. Because of limited virtual interviewing capacity, the Office of Undergraduate Admissions will prioritize interviews for students for whom the Admissions Committee needs more information. Interviews will remain optional, and students who do not receive an interview will not be disadvantaged. Interviews for First-Year Applicants | Yale College Undergraduate Admissions
I think they did this in response to the significant increase in apps. They don’t want to burden alumni interviewers with a wasteful exercise (each interview takes me at least an hour and a half of interview time and I spend around an hour or 2 to write each report). Then the AO has to read each report. It might take them 5 minutes to read and note an assessment but that aggregates to about 90,000 man hours.
If you have well below average stats for Yale and you do not get an interview, time to move on. If you get an interview, you will still likely not get accepted based on the numbers. The school completes about 18,000 interviews annually and only accepts around 2,100 annually. Not all of the acceptances had interviews (could be major hooks, some no doubters, unavailability of interviewer for that region, even by remote). So just by the numbers, somewhere around 10% (probably less) of applicants interviewed actually get accepted.