Maybe for the same reason why is not this year Mercedes E successor the last year´s S class?
You are clutching at straws with this same price thing. Its the die size and codename, what matters, when separating GPUs into product lines, not the marketing name.
You could indeed claim the actual performance is more important than die size, but funnily, these 2 are connected. If the relative perf difference between 680 and 580 was equal to relative difference between 580 and 285, 285 and 9800, etc... you would have an argument that die size does not matter. Except that did not happen. 680 was only cca 1,3x of 580, far cry from expected 2x. Unsurprisingly, it took 550 mm2 Titan to bring that performance jump. Which was priced at 1000.
So yeah, i am making that claim. Its the reason why 680 was not a successor to 580 and why it had no business to be sold at the same price. Well, it would have no business in ideal world, with proper competition. Clearly in this sad reality it sold pretty well. Be sure though, i did not buy it.
I agree with you that Nvidia does not give a crap. But they will keep hiking the prices and ultimately kill their own market altogether, cause the price of a new gaming PC will become outrageously high compared to consoles. Its already happening.