Sounds like the people you know don't want to do entry level reading on a $1000 purchase.
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.
Why are we suddenly expected to do more research on various models when part of the reason why the iPhone was successful was due to it's simplicity?