How competitive/ cut-throat are UCSD, UCLA, and USC pre-med?

These three so far are top 3 on my college list and looking to know which school I can best become a competitive med school applicant at. UCLA and USC, from what I’ve read on other threads have roughly 50% med school acceptance rates and UCSD a little lower. I know the curve is really tough at UCLA, but theoretically, as long as I have good MCAT scores, EC’s, and stay in the top half/ middle of the pack, I have a good shot at med school. How cut throat are these schools? I am aware these are pretty prestigious schools in their own right, especially the last two, but is it really that impossible to keep up. I am a 4.0 WGPA/2180 SAT student in plenty of honors and AP coursework. I know retention rates for pre-med are scarily low, but if one applies oneself and achieves a mediocre gpa, are these schools worth it?

As a parent of a UCLA Regents scholar (entering UCLA last year with 4.65 GPA/2370 SAT) I never thought the pre-med could be so challenging for her as well! But it is really cut-throat competitive, to the degree which I sometimes feel she could have been perhaps better off if she had gone to an easier school such as LMU (where she had a full-tuition scholarship offer as well)!

The competition in top tier UC’s is intense, especially in the medical/health profession fields. I had mentioned in a couple other threads, I know of someone who had a 3.6 GPA at UCB and got into UC Davis’s medical school within the past 2 years. The point is that if you do fairly well at the top tier UC’s and assuming your MCAT score is good, you’ll should have a good shot at a medical school.