The San Francisco example reflects not only a difference between Simplified and Traditional Chinese written forms but also between national naming practices. My understanding is that Mandarin speakers in the PRC and ROC use a coined name with its own history, while Cantonese speakers in Hong Kong use a straightforward transliteration, but Chinese speakers in the U.S. don’t necessarily cut along these lines cleanly.
These distinctions are captured to some extent in subkeys such as name:cmn-Hans and name:yue, but it remains valid for a user to request a map in Chinese (zh). Some software will automatically fall back to a Mandarin name in Simplified Chinese, owing to market realities, but that would be somewhat ironic and politically charged for San Francisco. Last time I checked, even proprietary map vendors in the PRC label it as both 圣弗朗西斯科 and 旧金山.