I would normally say that I don’t think CA even has the authority to ban 100LL since aviation is interstate commerce and thus controlled at the federal level. However, with the destruction of the Chevron Deference by the SCOTUS, that may give way to actually allowing this ban to go into effect.
This just means that like it or not, there has to be a drop-in replacement for 100LL, or GA as we know it will end in 2030. And such a fuel does exist right now, if only we can get it to be distributed to the airports.