I don't know, would you intuit the model called the X or the XS (read: "excess") as being the bigger, better phone? How many others might have thought it was "Xtra Small"?

And even if you knew the XS was the refresh, would guess the XR preceeded or succeeded it? R comes before S, so maybe S is the newest?

Personally, the X naming feels like kind of a gaff.