Yeah, you might not have Hearst Castle in your timeline as a lot of Hearst's wealth came from Mexican oil and timber, mining too, so they'd almost certainly be far less rich to build San Simeon.
San Francisco originally has the Gold Rush but so much of it's growth is as the primary U.S. port serving the Pacific and Asia, through the Pacific Coast Mail Steamship line particularly...so think about all of the trade from and with Hawaii, Alaska, Japan China, Korea, Vladiovostok and Dalian, Korea, Vietnam, Indonesia, Australia, New Zealand, Phillipines, etc. and that's a tremendous growth engine. The Mexicans would be better positioned to compete for that trade when tariff policies and rates were much more significant...might even trigger a Mexican ship-building industry at San Diego or Long Beach to serve the Pacific Trade which again would be a big economic building block for Mexico and not that big of a hurdle in that transition era of wooden ships and sidewheel steamers that it would be a few decades later.
Disney came to California from Kansas City which at that point was only behind NYC as the animation capital of the U.S., maybe he'd have stayed put. Maybe he'd have hired Harry Truman or Robert Heinlein there in Kansas City, Truman becomes the studio boss and Heinlein invents and adapts camera and special effects technology with that Annapolis degree.
Just about anyone in old Hollywood would take some different turns but especially the ones who grew up in Southern Cal in OTL (if they existed at all!)
Invasion of the West Coast by anybody requires a logistics train that no one had except perhaps the Soviets in the Cold War (getting the Soviet Pacific Fleet across anywhere but Alaska without having fatal trouble with SAC bombers, Rickover's subs, and our carriers and land-based aircraft would have been unlikely...Meiji Japan, Chiang Kai Shek's slice of China, Mao, Stalin...easier pickings far closer and again, just not the navy or merchant fleet.
I wonder about Asian immigration to Mexican California. The U.S. was treating especially the Cantonese Chinese workers very harshly and had them there as extremely temporary "guest workers" for the most part and the Japanese didn't get much better treatment until long after 1945, while the sparse population accumulated by Spain and Mexico in Southern Cal over 200+ years would encourage allowing Asian immigration there, especially skilled labor, trading and shipping office branches, banks, smelters/refineries, shipbuilding/repair, etc. a hundred years ahead of the U.S.'s discovering the impressive human capital it had been overlooking. That'd draw a lot more Pacific trade in itself, San Diego might indeed become the dominant city on the West Coast of the Americas as a result.
It's really intriguing the more we kick this around.