Essentially, yes, and it didn't change- it's just that agriculture is no longer the biggest sector of the economy.

Californian agriculture has always been more like Argentina than the midwest, if you know what I mean. When CA became part of the US, most land was already "claimed" more or less legally, although many native/Latino californians were disenfranchised of their land, this was mostly done to the benefit of large landowners rather than small scale homesteaders. Until the growth of industries relying on union labor, political control in california was dominated by landowners and the capitalist class.

Arguably it still is, but now a lot of the capitalist class in california is involved with finance, entertainment, or tech companies which are all so socially liberal they still tend to be liberal and vote Democratic.