Both Berkeley’s and UCLA’s Common Data Sets state that “Level of Applicant’s Interest” is not considered. https://opa.berkeley.edu/campus-data/common-data-set
https://www.apb.ucla.edu/campus-statistics/common-data-set
I don’t believe HS yield factors into acceptance and I don’t believe either school “routinely” rejects students with perfect stats. I would be interested in where you found that information.