Not an experienced Cabezon fisher but I have been fishing around here since 1960 or so. I have caught 1. IMO you are much more likely to catch a Rock fish while Cabezon fishing. Don't know for sure, but the Cabezon restriction could have something to do with protecting Rock fish. I have no doubt that like every other fish around here, the population is low.
Not protecting Cabezon now could just worsen an already depressing situation. It's OK to be a conservationist without having to be told by the Govt.