California’s Office of Health Care Affordability faces a herculean task in its plan to slow runaway health care spending. The goal of the agency, established in 2022, is to make care more affordable and accessible while improving health outcomes, especially for the most disadvantaged state residents. That will require a sustained wrestling match with a sprawling, often dysfunctional health system and powerful industry players who have lots of experience fighting one another and the state. Can the new agency get insurers, hospitals, and medical groups to collaborate on containing costs even as …