Wow, how I completely disagree with that. A lot of people enjoy the show, a lot of people enjoy it for what it is I mean, not looking for a "almost-perfect" version of the character as "Dork Knight" seems to be. "It does not have a future", this is what people were saying in season one. Now it is season 10 (almost) and it is still the same argument it seems. And IMO, I think it is better in television, it allowed to develop Clark personality(ies) for real, instead of having everything in one movie. I may like the new movie, I do not know, but I think you reduce the importance of Smallville on the Superman mythos.
As for my opinion about the topic, Nolan or not, for me, Smallville will not "fade" at all. I do not need a new toy every once in a while, so Smallville has been a great great serie, and I will always like it, Nolan or not. It established the character, especially for me who watched the serie since day one. The best thing about it, is that it allow (at least me) to enjoy different versions, because Smallville has been a great pot full of good ideas like Superman tas, or Lois and Clark or Superman the movie, or Returns.
And I disagre about the fact that it will be remembered as "Lois and Clark", or maybe for those who watched the serie only when they begin putting Ollie, or Aquaman, or Lois in the show. For me Smallville is more about the farm, the young years, the (sometimes boring) 5 years of "I love Lana". Not only the metropolis years.
This serie is really great, and ten years of building the mythos, it is huge, no way I'm going to forget it. I love the show, I will still like it in 5 or 10 or 45 years. I do not need a "ultimate" version of the character, especially since I'm not fan of Batman vision of batman, in comparison.
I loved Superman Returns, I loved Smallville, both in different ways.