Location for many students is an issue along with the preconceived idea of it being a lower prestige UC and having a high acceptance rate especially since it is the ELC deferral campus.
This link is worth reading about what UC Merced has to offer: https://talk.collegeconfidential.com/t/a-very-honest-opinion-on-uc-merced-from-a-uc-merced-skeptic-2022/