Well, I used to lurk this forum A LONG time ago before I joined (2009)
and a lot of the early stories were, well, like you said, sort of proto-story.
In the modern incarnation of the subforum, it oddly seems
much healthier and active than it was, say when Civ4 was out in full swing.
In my opinion, I think it's because of an adopted consciousness among visitors
to the subforum; what I mean specifically is that if we compare posters now
and posters then, storytellers today have acquired a much higher retention rate
for their stories than storytellers back then.
If you notice too, a lot of promising stories sort of just died right in the middle,
right in the subforum's formative stages. Likely from lack of attention, because
the proper audience had not formed yet.
People don't really post one-shot "hey! check this out! this spearman killed my tank!"
sort of stories anymore. People nowadays are more interested in keeping to their
stories longer (generally). And people keep coming back to check out the stories
because of it. Problematically though, it's harder to DRAW new users into the subforum
compared to the mainstays like the modding forums, Strategy & Discussion &
General Discussion. Most people only come to S&T through stumbling upon it really.
And that was really how S&T must've started out.
People talking about random stuff (hey! i just lost to this, lol!)
at the watering hole that was S&T.