I should have phrased better that I think the Trolloc Wars (which went on for about three hundred years, and covered more or less the entire continent) would justify a massive population drop; what puzzles me is the sense that there's been a further decrease since then. Subsequent conflicts like the Aiel War aren't major enough to explain it, and although you have sort of ongoing endemic conflicts like the fight between Arad Doman and Tarabon over Almoth Plain*, those are kind of self-correcting; when you have few enough people, you can't sustain that fight anymore. And besides, Almoth Plain isn't depopulated; it's just contested.

Possibly I just misunderstand Jordan's chronology, and what we see now is actually a recovery from the post-Trolloc Wars days. It doesn't really seem like it, though.


*Not that I expect these names to mean anything to you; it's more for anybody else who wants to hop into the discussion.