The UAW is a mess, no doubt, filled with corruption. As for California and Tesla, Tesla has gotten away with a lot of bullshit, and they're just getting nailed in court for it. This isn't the state. This is just laws. Yes, other states are often easier to deal with as an employer. However, other states also make it easier to treat employees badly. So I have to give my employees sick hours. I have to give them breaks. I have to treat them as employees, not contractors. Somehow I can do all that, pay them far more than minimum wage, treat them with respect, and make a living. We may move somewhere else cheaper to retire, but I doubt it will be as nice... except for traffic.
It's not just the factories moving, the skilled craftsmen are leaving too. They end up with more disposable income, larger homes, more free time, and cheaper tuition for their kids.
There is an illusion that the standard of living for those in the mfg'g sector is high in California. It's not. Many other states pay the same with a far lower cost of living.
I give my team full medical including their families with no employee contribution, pension, tuition reimbursement, up to 4 weeks vacation, Free-Lunch-Friday, childcare area, flexible hours.
None of this mandated by California. I do it because I treat my team the way I want to be treated. And so they don't flee the state, and it's worked. My average tech has been with me >15 years.
But for my team members that are nearing retirement, most are leaving the state to stretch their dollars.