Get everyone out? No.

Prepare? Absolutely. I can't speak to the state of California's earthquake preparedness, but there should absolutely be supplies and equipment stationed throughout the state in preparation for it. It is my understanding that San Francisco, for example, has water cisterns throughout the city for fighting fires in such a scenario.

It is dumb not to prepare for disasters we know will happen.

California absolutely can and should prepare for the eventuality of a large earthquake in the area (and they are, as another replier pointed out). Permanently evacuating the whole area maybe not.

Why is disaster preparedness at all controversial?