It's true. However, if you have a chance to lure a Demetris Robertson, I think you have to go for it, feeling confident enough about Cal and Cal Football to believe that he's gonna love it here.
We'll almost certainly never have the national cachet that Stanfurd does, but we can have some of that, being a top academic school in a nice area, with great weather. The staff always needs to be scouring the nation for the possible right fit, without expending too many resources that could be used for West Coast recruiting.
While we always want to "own our own backyard", SoCal's probably always gonna be our biggest target, because of the sheer number of athletes (which is why UCLA is pretty much our biggest recruiting rival). In fact, the-rest-of-the-Pac-12-footprint (minus SoCal) is probably going to provide us with more players than the Bay Area. Just look at the lists every year of top Bay Area prospects: Usually only a handful of four-stars.
Bottom line, wherever you can get a pipeline going, you do that, but, yes, loooong pipelines are more likely to have leaks.