If somebody reputable ever claimed that STGs deal less damage at max range, that definitely wasn't Cruzz. At least that's what the DPS charts generated by him would indicate.
I don't remember the exact DPS curve of STGs vs Volks Kar98, however STGs will certainly beat Kar98s all the way up to range ~32. Very likely all the way up to max range (35).
Note that none of the DPS charts so far account for the burst pattern of STGs. The focus-fire thingy means that STGs (like BARs) can still register a hit, even if their native accuracy would say otherwise.
You're right, it wasn't Cruzz. It was a conversation with yourself. Here is what you concluded after a few of us did tests.
"I think you have a point, and that was a mechanic I was not aware of beforehand.
Rifles and LMGs have the "focus_fire" property on, which I assume is what turns singular LMGs into death-ray-laz0r beams.
However, SMGs/assault rifles don't have this property on. This is probably why, even though the affected units deal a ton of DPS, they don't immediately snipe models. I have no idea, however, how the damage is spread (do they affect multiple targets within the same burst or not)."
So as I said, dps does not always translate to statistically higher chance of winning an engagement. In this case the kar98 drops more models at long range and so is the more deadly weapon at that range.