In truth it's probably like this:
Well it was a QB:
Easiest to play, less work and it's random. Probably because there are not a lot of well "designed" maps out there. Also it looks like players tend to shy away from playing "designed" scenarios for ladder points. Don't know why but it looks that way, maybe fear of getting a lopsided scenario.
1. I bought some units, and he bought some units:
Probably because everyone purchases the "usual" units. How many players have actually bought unique units like a Hummel / Brumbar / KingTiger / etc.? Why make a big deal about common units PzIV, T-34's etc.
2. The map was the usual random hodgepodge:
Not enough designed maps out there, but has anyone bothered to delete the designed units from scenarios and just use the map (good ones) for their QB's?
3. I setup, he setup:
Unless the objectives & terrain are "special" it's a normal setup.
4. We both moved...
Again unless something about the game is interesting not much here to talk about, "I tried to flank him / I rushed the VF's..."
5. I lost some units, he lost some units:
My PzV got him in one shot, another dead T-34, ho'hum.
However- "My fanatical flamethrower dude ran out 40m into the open to torch a KingTiger," now that is news.
6. The guy who lost more units probably lost the game:
Now- My sole Hertzer took out 10 SU-122's- lets hear about that!
7. The guy who controlled more VF's probably won the game:
Enough said. Not too many other variables here.
8. End of AAR:
Unless the game is a designed scenario a players objectives / motivations in QB's are pretty common.
And of course: when you are playing several of those ho-hum QB's at a time and they are just a few in a long line of similar games played & to be played it's just not worth the effort to write up something special for another "common" game. (Note your opponent however may make the game not common at all!)
I believe it takes a good scenario background story and a real "in game" reason to be engaged personally in "this" tactical battle to warrent the energy to write up an AAR.
Notice the remarks in the "Report an Endgame" section, few QB's even warrent a "Good/Bad" comment & if they do it's usually about their opponents good play. Why go on at length about something no one else will ever be able to play themselves. (Too Random).
However, designed scenarios can justify comments and AAR's as you are reporting on a singular game situation everyone can play. Plus your comments can have an effect on if someone else plays it and how well they can do.
AAR's do take time and energy, most players I suspect, like me, are doing good just to have decent time to study & play a turn much less find the time to write about what we're doing in a entertaining & readable manner.
That's why those players that do find that time are greatly appreciated.