They're moving in part because CA continues to push out businesses that require unskilled labor, through a combination of taxes, minimum wage hikes, regulations, and other roadblocks. Generally it's dressed up as a Good Thing, but I'm not so sure.

CA has the highest poverty rates in the country, along with the highest taxes. SF is rich as all hell, but can't keep feces and needles from littering the sidewalks or car windows intact. Cupertino had virtue signaling signs up supporting undocumented immigrants and welcoming them to their city - but their housing policy shows only the rich of any race or creed are welcome.

All the while places like Houston are booming, with development happening everywhere, affordable housing, diverse population, and jobs.