The analysis comparing GPU flagships and price/wattage is somewhat shallow because it hides another thing that has been going on, the reduction of fundamental specs of the various classes of card. It used to be the case that a x80 chip meant it had a 512 bit memory bus, that it was ~500mm^2 die and hence a fully maxed out GPU and you got all that for ~$400-500 or so. Then the 680 came out and its specs were more like an x70 card from the prior generations, its only 294mm^2 and a 256bit bus, it was a rename of the lower class card, they never produced a flagship for that particular generation and some of that degradation in specs carried over to the 780 ti as well which now only had a 384 bit bus but its die size was ~561mm^2.
An RTX580 is now 378mm^2, which is about an x70 in pre 2012 terms and 256bit bus which is also x60-x70 class.
That process has resulted in the titans and the x90 and the x80 ti all slipping above the x80 as its specs gradually decline and its price is still going up compared to the historical picture, enormously more than inflation. During the same period CPUs on the other hand have stayed fairly similar in price with a steady increase in performance at a price point. That 680 oddity in the historical area was the moment things changed and AMD had a big part to play in the reason why with their 7970 being priced so much higher. This process started then in 2012 and its been getting worse as time goes on.
The analysis comparing GPU flagships and price/wattage is somewhat shallow because it hides another thing that has been going on, the reduction of fundamental specs of the various classes of card. It used to be the case that a x80 chip meant it had a 512 bit memory bus, that it was ~500mm^2 die and hence a fully maxed out GPU and you got all that for ~$400-500 or so. Then the 680 came out and its specs were more like an x70 card from the prior generations, its only 294mm^2 and a 256bit bus, it was a rename of the lower class card, they never produced a flagship for that particular generation and some of that degradation in specs carried over to the 780 ti as well which now only had a 384 bit bus but its die size was ~561mm^2.
An RTX580 is now 378mm^2, which is about an x70 in pre 2012 terms and 256bit bus which is also x60-x70 class.
That process has resulted in the titans and the x90 and the x80 ti all slipping above the x80 as its specs gradually decline and its price is still going up compared to the historical picture, enormously more than inflation. During the same period CPUs on the other hand have stayed fairly similar in price with a steady increase in performance at a price point. That 680 oddity in the historical area was the moment things changed and AMD had a big part to play in the reason why with their 7970 being priced so much higher. This process started then in 2012 and its been getting worse as time goes on.