I used to bike a lot in SF. Then I realized that in less than a year I had a roommate shatter an ankle on market street and need surgery, a friend get hit by a bus and had to wear a neckbrace for months, another friend shattered a shoulder and also needed surgery, another got doored and had back problems, and I also got doored, but was fine. Though my bike was messed up. Great bike culture, but not very safe.
Californians in general drive both better (more safely) and more courteously than drivers in Minnesota, but even with the bad weather here, some Minnesotans bike. I feel much better when my wife is on a designated bike trail than along a roadway that has car traffic.
LA has a terrible bike culture. I learned to hate biking down there, and it's only now up in SF that I've started repairing that.