Some bubble areas were more bubbly than others, but the nation as a whole has experienced this housing bubble.
San Diego is no different from the other inflated cities, all of which are dropping at this point. New York didn’t have as much of a bubble to begin with (very high salaries had always supported a very high median home price in the city), but even so, their prices are also now dropping. The SF Bay area is also dropping like a rock right now, just not quite as much of a rock as San Diego, Phoenix, Miami, and Las Vegas, which is why those cities are getting the majority of the press.
San Diego did hit the hyperinflation phase of the bubble about a year earlier than most of the other cities, and we also topped out earlier, but at this point, the Case-Shiller indexes (and the other indexes) now have pretty much all of the bubble cities in free-fall with regards to prices.