Interesting website.

"Semiconductor Fabrication (7nm/5nm)

The main processor requires ultra-clean rooms, toxic gases (arsine, phosphine), and chemical etching. No new fabs have been built in CA in over a decade. Intel, TSMC, and Samsung all build elsewhere."

Phosphine is pretty nasty stuff. California was full of EPA Superfund sites when the government got stuck with cleaning up all the toxic waste. Politicians and voters went, "Eff that!" after manufacturers left the state, but left their barrels of shit behind.