To be fair to the editors, the inch measurement is just coming from Apple, that's how they refer to it. If the editors converted the model name into centimeters

To be fair to the editors, the inch measurement is just coming from Apple, that's how they refer to it. If the editors converted the model name into centimeters they'd be using a different name than Apple, and probably losing some search traffic as well. But I feel your pain: it's not even a great description, because the screen isn't 13 inches, it's 13.6 or something like that.