I live in California. Most of my friends and family live or have lived in California. Several have moved out in the last 5 years, all for the same reason: It is really expensive here. Not politics, not immigration, just plain old money.
There is a housing shortage that has been ongoing for years, inflation has kicked the crap out of peoples wages, and boomers are retiring and transitioning to fixed incomes. Some people are cashing out their incredibly valuable homes and moving to cheaper states (often times selling to corporations that turn their homes into rentals at inflated prices, which is a whole nother problem). PG&E also managed to burn down a couple of my friends homes. They had to move out of state simply because there was nothing available for them to buy or even rent. That is what you get when an infrastructure provider cheaps out on maintenance in the lowest income area: they burn down all the affordable housing.
Many people still *work* in California though. Remote work has changed the calculus on homeownership for some of my friends. They moved out of state, kept their jobs, and can now afford to buy instead of rent even though they were almost 'low income' here. Oddly, I have seen more than a few move a second time. I had family retire and move to Texas only to move to Oregon after a few years. They couldn't take the bipolar weather. Summers where its 100 percent humidity and 90 degrees at 2 AM, winters where the roads all freeze, storms that come out of nowhere, rattle your house for an hour, and then its sunny and bright an hour after that. I also had friends that moved to Nebraska. They didn't last 2 years before they moved to Colorado to escape the boredom. They are avid outdoors people. Why they thought eastern Nebraska would be a good idea I don't know. A lot of the old folks I know have moved. Some even moved to Mexico for cheaper medical care. Mostly its the same story: costs. Healthcare is expensive, housing is expensive, gasoline is expensive. It all adds up.
I tell you what though, the infrastructure is hugely different in California. I've heard all the complaints of living in flyover states. Terrible roads, no sidewalks/bike lanes, non-existent building codes, non-existent city services, crazy neighbors, you name it. Friends in Tennessee said there was no water, sewer, natural gas or even garbage pickup in the town they moved to (20 minutes form Nashville). Everyone was on septic tanks and wells. As you can imagine, that sometimes caused problems. A few times a month they would load up their truck and drive their garbage into the city for disposal. Some of their neighbors would just burn it in their back yards. Technically illegal but not enforced. Lovely. A family member that was a retired contractor spent over a year trying to find a home in his price range that wasn't, in own words "a deathtrap waiting to catch fire", in the Texas community he wanted to move too.