The most difficult part of the process is that California would need the approval of 3/4 of the states.

I believe that Republicans are pretty close to controlling 3/4 of the states

I would assume that, besides California, every red state would vote for CA secession

If such an event actually occurred it would be a long time before a Democrat ever won the presidency in a Californialess United States.

Every illegal in the Californialess US would flee (forcibly or not) to the illegal immigrant loving California. That would lead to an exodus of many working familys to the new Californialess, illegal immigrantless US

Sounds like a death spiral for CA if you ask me.