Most people don't realize that because it's not true. The air quality of the combined statistical area of San Francisco is worse than that of the CSA containing

Most people don't realize that because it's not true. The air quality of the combined statistical area of San Francisco is worse than that of the CSA containing Pittsburgh, but pollution in the expansive San Francisco-Oakland-San Jose CSA is centered elsewhere, whereas Pittsburgh is the pollution epicenter of its CSA. This is due chiefly to its geography, not some kind of moral failing. San Francisco has very favorable geography for air quality. As for your linked article, that seems irrelevant. Nobody thinks Hanford, CA is an upcoming tech hub.