I think, right now, inflation/deflation of pax demand is a global thing, so it will effect everyone equally. On the flipside, while certain routes had HUGE hits after 9/11, when you take the world as a cumulative whole, it mitigates the damages by spreading them equally over everyone.
The effect really isn't that big. Not in real-life (for very long) and certainly not in AWS.
All it effectively did was knock back air traffic 2 years to 1999 levels. In the grand scheme of this game and how fast time passes, that's extremely minimal and it ultimately impacts little. It'll hover the same levels for 2002 and 2003, then skyrocket in 2004.
In the real-world, where margins are low single-digits, a drop of 10% in traffic is a big deal. It's the difference between a profit and cash pouring out of the coffers. And, of course, we saw the effects of that.
In a game where margins are 15, 20, even 30%; a 10% drop in traffic hits the bottom-line, for sure, but it's not sending airlines cowering into bankruptcy.