I really don't think Steampunk is tied to the iPhone in any way. "steampunk was a cultural response to the ultimate technological zeitgeist, the iPhone" is a pretty bold claim.
It's like someone picked two topics out of a hat (iPhone, Steampunk) and was tasked with writing an article about them. iPhones (and smartphones in general) were definitely a cultural phenomenon, but there's literally nothing tangible connecting them to Steampunk aside from the author's shallow, fluffed up wordsmithing.
i think it's tied to skeuomorphism, i.e. giving advanced technology a more tactile sense. the author's neglect of this concept makes these concepts harder to parse, since it what tied the previous and current design eras.