Few small cities in the Bay Area have rent control ordnances, including Mountain View, which is the city that originally wanted Google to build all new offices

Few small cities in the Bay Area have rent control ordnances, including Mountain View, which is the city that originally wanted Google to build all new offices and no residences. So no,it's not Rent Control that is driving commercial-only zoning restrictions. Perhaps it's the fact that commercial office tenants pay property taxes, but require few city services in return -- no schools, limited police and/or fire services, little demand for parks or recreational activities, etc. Even in SF, only buildings built prior to 1979 are covered under rent control rent restrictions, so rent control wouldn't affect new zoning decisions.