Based on https://www.aamc.org/download/321466/data/factstablea5.pdf that is linked above, it looks like California is not the worst, but is not good either, particularly for lower-cost in-state medical schools (and California public medical schools have higher in-state costs than those in many other states). Lower cost in-state medical schools can be found if you can move and gain residency for them in New Mexico or Texas, though medical school applicants in those states get shut out (of any medical school, including out-of-state or private) at similar rates as those in California. But some other states (particularly in the northeast and some other western states) would not be an improvement from a pre-med standpoint compared to California.