I think it may have more to do with the article being written by a native French speaker than sexism.
One of my friends routinely says things like "a woman has rights to his body" when speaking in English because in French possessives agree with the object not the subject, and the French word for body, "corps", is masculine.
In this case, since iPhone starts with a vowel, in French you'd say "son iPhone", so "his iPhone", perhaps.
Alternatively, in French you also always tend to the masculine form in the general case, so maybe that's it? It just strikes me as extremely unlikely that anyone would think, consciously or otherwise, that women don't have iPhones.