In a photograph or painting, no actual narrative can be provided by the artist or work. There is no temporal component in a still image.
Each medium is different, has different abilities & strengths. Not every medium can do everything all other media can.
You know, I think I would agree with you 100% if you substituted something like "Communicates" for "Tells a story". Everything we make communicates something to a viewer. It's just not always a narrative.
First, I agree with you that one medium may do certain things better than another: it's what the Modernists got hung up on - "medium specificity". That said, just because a medium's not great at something is not a reason to not use it for that purpose...
I think what we need to agree on is the meaning of "narrative".
First, why does a narrative have to imply the passage of time? I know Wikipedia is hardly the fount of all knowledge, but it does accord with the usual definition of a narrative: "A narrative (or story) is any account that presents connected events". Note that Wikipedia goes on to say that the passing of time is not part of the definition, merely an aesthetic convention.
A narrative is thus nothing more than the outcome of the perceived relationships between the components in a made object - such as a photograph - regardless of whether these relationships are intended or accidental.
"Communication" is way too non-specific and broad a concept - meaning simply the conveying of information.
Photographs tell stories - narrate - because we perceive a network of information, of cause and effect. Let's take one of my photos:
There's undeniably a story here - and in contrast to what you say, it involves time, albeit implied. What can we say about this picture? At it's most basic: "A woman crossing a road in a rain shower". We can add elements to the story, reading structure from the picture: "an unexpected shower" (she has no umbrella, and it's not raining in the distance), "in winter" (leafless trees), "in the afternoon" (a low sun), "on a hill in a town" (we're looking down on buildings, and villages don't have tower blocks). She's obviously a young woman, and a dog owner. There's plenty more information - for example, we can see that it's a fairly recent photo, certainly taken post-1960 - but that will suffice.
So, a simple and likely narrative from these interrelated elements is simply: "The girl was walking her two dogs one winter afternoon in town, when the heavens unexpectedly opened; head down, she scurried across the puddled road, and on uphill."
We can of course embellish this story: we suspect she was feeling miserable, and that she changed her sodden clothing in relief once home.
Writing is more suited to narrative, so would tell a similar story more completely that would be interpreted with less (but always with inevitable) variation by readers. But that does not change the fact that this picture tells a story, albeit leaving a lot implied and much to the imagination, so the stories associated with this photograph - as with most pictures - will splinter and multiply readily for different viewers.
