The progress of wargaming in recent times

[Popsical]

Let me chime in....
IGOUGO isnt dead, for the simple reason its the easiest system for game designers (especially lazy ones) to implement, its also the easiest for new gamers to grasp. Some systems use the "all move, all shoot" and others the stricter "I move I shoot, you move you shoot", but eiither way its a simple system

Systems that split it up (based on skill levels let's say) can be more "realistic" but they are more complicated for the new player to grasp, and the concept of simultaneous action confuses some. (yes I'm dead but my shots still count)

Its interesting that you say non igougo is more complicated. The rules to each of the games i mentioned earlier are far smaller and simpler than say 40k or WFB. Im not saying that all igougo is more complicated, but the core rule books of the current big guns (warmahordes, 40k, WFB) are much bigger and more complicated than say SoG.