By limiting who says what, Bethesda doesn't need to record 16 variations of every line of "general" dialog, and you can bet that you'll still have no problem hearing most comments 20 times a day. Make slightly different "versions" for each of several races, with their own slightly different "viewpoints" on the subject by race or six, or use similar but different subjects instead. It takes the same amount of storage space and recording time and the same expense to voice act as if it's all the same line, so why not "change it up" a little bit?
In both games, there were a lot of repetitive "rumors" and other "constant" topics that got tiring to wade through, with a distinct shortage of "meat" in between. The lack of unique dialog in OB was worse, because there was far less of it to begin with. MW's topic lists gradually grew as you "unlocked" new topics, until many of the NPCs became little short of walking encyclopedias, which was a bit excessive at times (although very appropriate for speaking with the few Savants in the game), whereas OB's NPCs mostly had nothing relevant to say, and not much irrelevant either.
Oh, this time, can we have a voice actor who doesn't call the dark elves "Dumbner"? (Same actor, same issue, in both MW and OB)
I never noticed that actor saying "Dumbner" maybe it is just the audio or more likely you . . .
They need additional voice actors this time though, variation is a must especially when it comes to old and young NPC's.