I think the main culprit when it comes to costs and could be wrong, is that need for better grahphics, the cost to improve 5% better graphics is exponentially growing, as to see a 5% difference requires far more effort, and it's this stupid need to look better rather then make a good game I think thats hurting things.   For me, I would rather the game look the same, but put the time and money into other things, better engine, more features, better physics and such.