I work in insurance and I concur with everything The Great Sun Jester said.
In my policy with USAA the most expensive thing is Comp and Collision, but it’s worth it because I know I couldn’t replace my car anytime soon.
California’s state minimums are only 15/30/5, and as you can imagine, $5000 isn’t going to do much good if you hit a new car, or multiple, so one should really have under-insured motorist insurance.