LOL,people have short memories.
The Geforce 256 and the 9700 PRO were revolutionary when they came out.
The Geforce 256 was not only the first DX7 GPU but also had transform and lighting hardware,unlike previous GPUs which required the CPU to do such operations.
When the 9700 PRO came out,it was considered a perfect card in every way and the first DX9 card:
http://www.anandtech.com/show/970
It was incredibly complex for the time and IIRC had the biggest GPU(in terms of transistors),but still delivered in performance and power consumption too.
Compared to what Nvidia released in the 5800 Ultra and Matrox had with Parhelia they were beaten in almost all metrics.
Both companies could barely compete with the 9700 PRO/9800 PRO.
Nvidia even jumping to a process node ahead,could barely compete with the 9800XT and it had far more memory bandwidth too:
http://techreport.com/review/5797/nvidia-geforce-fx-5950-ultra-gpu
Then there was the mighty 8800GTX - that card was a massive performance bump over the previous generation and was relevant for years.
The GTX970 and GTX980 are not revolutionary - they are refined 28NM cards with improved power containment and control mechanisms.
You might as well say the 8800GTS 512MB was revolutionary compared to the 8800GTX,as it had most of the performance but consumed far less power and was half the price. I had the latter myself too. The HD5850 1GB could have been considered revolutionary too,since it was released six months before the GTX480,overclocked well and consumed much less power than previous high end cards too. It was also cheaper than the GTX285 while also being the second DX11 card made.
HD4870 and HD4850 against the Nvidia cards. The AMD "small die" strategy which meant the prices on the GTX200 series collapsed,meaning people had awesome value cards. Nvidia was using 470MM2 to 576MM2 chips against 256MM2 to 282MM2 chips,so for the size the R700 was remarkable for its performance(plus it pioneered the use of GDDR5 too in graphics cards).
The revolutionary cards tend to have long lifespans.
The Geforce 256,9700 PRO and 8800GTX were considered fine for gaming for years and great examples of high end cards. You could argue they set the bar in terms of allowing devs to push shinier games.
Going down the range,for budget gamers,the 9500 PRO,6600GT,8800GT and HD4870 brought high end performance but for much lower prices.
Likewise the 6800 GT you could unlock to a 6800 Ultra.
It was the AGP 6800LE which was the best for unlocking - I had two. One unlocked from 8 pipelines to 12 and the other from 8 to 16. I had in-between 6800GT and 6800 Ultra performance for a much lower price.