The problem rests with the market. People are satisfied with rehashed FPSs,
a new Madden, and MMOs every year it seems.
You also have to consider that of course it sounds like there's a market if
you read the posts here. Except that HLP and GW account for such a small
fraction of the overall market, that you'd probably run out of decimal places.
EVE Online is the only real example of success right now, and it can only loosely be called
a sim for these purposes.
What they need to see is a resurgence in the SS genre by way of a competing product.
Jumpgate for example... if it took off then you'd have an easier time selling FS3 to the bean counters.
Add to the fact that the game developers are hurting in this economy, and consoles and mobile (the latter
being where the main focus is right now) are showing the most growth, and you have to see that PC
platform isn't the major leader if you want to capture the casual audience.
So there's some significant hurdles to over come.