Well from my perspective it's not that people hate California it's that they hate the influx of Californians in their state. Tons of tech people moved from San Francisco to Austin and now it's near unrecognizable. Austin a long time ago used to be a small city with a lot of charm now it's the tenth largest city in the US. It's not just Californians moving their but they are the biggest group and they are pretty loud about where they come from.

Everything gets more expensive, they bring some of their failed policies with them, and there are a lot of weird ideas that come out of California. I don't mean your generic lefty policies that may upset some old timers in Texas but like the weird transhumanism shit that tech people are obsessed with. It feels like a cult, another thing California is known for, and it's basically the opposite vibe of what Austin used to be. I personally have met a lot of Californians I really like but it's not hard to see the culture clash. Also when I say California I really mean San Francisco and LA, not like Sacramento or the other parts of California. It's the tech people, the Hollywood people, and the groupies they aquire. They leave California due to costs and it's somewhat chaotic nature but then start to transform their new home into California.

If you've ever met old timers in Texas you know great don't like change. They talk about building an overpass as a sign of the apocalypse. So that's where I assume most of the hate comes from.