Fwiw I don't think the California GOP needs to necessarily moderate (especially in the very Silicon Valley way many "moderates" think of) to win in a modern California. In most Latin American countries the right-wing are mental, and they don't have that much trouble winning. But conservatives simply can't use immigration as their crux issue. Or they will lose.
It's not exactly the right-wing Latin Americans who've moved to California.
Anyway the CA GOP is never going to win statewide again no matter how much it "moderates," unless it somehow "moderates" to the point of being left of the Democrats and continues staying that "moderate" for several election cycles.