Well, I lived in Hollywood for a long time, went to Spago's when it was still on the hill on Sunset and the Pizzas really did become the star of the show. That said I have eaten at California Pizza Kitchen and I must say it was a lot better when it first opened then what it is today. Quality has gone down over the year. That coupled with the fact that there really was not may places out here that made great pizza at that time back in the 80's and even 90's.
I must say though, things have changed. We have a growing trend of great pizza places in LA that rival NY. Mozza in Hollywood and Micheal's in Long Beach are very highly rated. The first one mentioned was started my the same chef behind La Brea Bakery. Micheal's in Long Beach makes a DOP margarita pizza and was recently rated by Zagat as the best in America. The one caveat is you have to still seek these places out. Don't go to Hollywood Blvd and expect to get good pizza, you will be very disappointed.