Universal healthcare can't work on a state level because of the free rider problem: people from red states could go to California for free healthcare anytime, while never paying taxes into the system. Californians would end up paying for healthcare for the entire US, which is unsustainable.

It works in Canada because Canada doesn't let sick Americans immigrate. But as a US state, California has no power to keep out sick red staters.

That's a fairly recent phenomenon (California was a Republican stronghold in Presodential elections until 1992, and longer for state executive elections.) And the tendency toward balance that is asserted for FPTP is national; subordinate jurisdictions aren't expected to follow it even by people who adhere to the theory.

> who have a super majority in the legislature and the Governorship, and can pass any legislation they want without a single Republican vote or amendment. That's been the case (with a brief stint by Arnold) for multiple decades.

No, it hasn't; Democrats have only had supermajorities since 2012, and Gray Davis (1999-2003) was the only Democratic governor between Jerry Brown (term ended in 1983) and Jerry Brown (term starting in 2011.)