you greatly overstate the case... California is a massive state, and the bulk of the state geographically anyway can claim very real grievance against their government.... the other states you list, not so much.
If California were to break, particularly along those lines, No Democrat would win the White House again.
I think you are overestimating. Cali has 55 electoral votes. After the split New California would get about 15 from looking at the map, plus two for their new Senators. Old California would get 40+2. Seventeen reliable Republicanelectoral votes would not guarantee GOP victories in all future POTUS contests. Obama won by more than that, for instance.