What gives you that impression? Unless you're looking at the pre-9/11 grid powered by Enron™, rolling blackouts aren't a big deal in California. I think since 2001 there was a single 2 day event limited to certain regions, I don't know anyone personally who lost electricity due to rolling blackouts.

The CA grid has also scaled up battery storage surprisingly quickly. A few years ago it was in the single digit mWh, not really a meaningful fraction of the grid. Now it's measured in gigawatt-hours.