Wear does not equal polish. Look at how sharp the notches in the case back are. Major clue.
I would tend to agree that the case back looks less polished, perhaps instead merely “worn” as you call it. Notice in particular the dings, nicks, and scratches, and how the edges of the case notches are variously dinged round or still straight, but the nooks of angles crisp (because what could get in those nooks?):
But
casebacks need not be “polished” when instead the more visible portions of the watch are the intended target of “sprucing up.”
As with the caseback, “wear” takes the form of dings, scratches, and perhaps some un-uniform softening of points (that stick out and get rounded) or un-uniform and sporadic softening of an edge here and there.
Compare that with the OP’s posted watch case itself, the “edges” (if they can be called that anymore), are uniformly rounded off, but importantly (1) to include rounding at even the protected nooks between angle changes, and (2) unlike the caseback the lack of scratches, dings, and the like:
Whereas, here is a NOS case’s edge work:
Whatever one chooses to call a case that is now uniformly marble-smooth at all edges and even recessed nooks, where it was once before a razors edge, that is this watch. Calling it “polishing” or “wear” is perhaps neither here nor there.
But to me, the “wear” to the case back instead emphasizes a contrast against a case that has been polished.
