I know nothing about California so please correct me if I'm wrong.

You mention significant hydro and solar capacity in California. So minimal carbon externality: lung disease and climate change. If you consider that externalised cost into the cost of electricity elsewhere, does not California and other renewable-rich electric grids fare more competitive on price?

E.g. the problem is not the expensive renewables in California, rather, the problem is that the cost of declining human and animal health and climate change is externalised for the fossil fuel.