It is actually quite easy to be nostalgic for the Cold War. It was a time period in history where the world was more black and white. America and NATO were the good guys, and the Soviet Union and the Warsaw Pact nations were the bad guys. America also seemed like a greater nation back then.
I think that the success of such television shows such as The Americans means some people are nostalgic for the Cold War. I think the subject to the Cold War is always going to be something people are interested about. But I think people also prefer that it is set in a ficitional setting.
No, the success of the television show "The Americans" does not mean that people are nostalgic for the Cold War, because people are still appreciative of how much more secure the post-Cold War era is. People do not necessarily want to return to the era just because they appreciate a television show. World War II shows are popular too, and we don't want to go back there.
From the begging of time there have been conspiracies, and there have been conspiracy theories (Did America really put a man on the moon? Was Kennedy working for the mob? Did the government set up the assassination of Abraham Lincoln? Did aliens build the pyramids?)Some sound almost plausible while others sound just plain crazy. Another draw of the show is the turmoil. These are spies looking to take down America who lie every minute. But you get pulled into their personal lives and hope they pull though despite it all.
The Americans is a fairly popular TV show. However one show being popular does not mean that people are nostalgic for the Cold War. Vampire and zombie shows are really popular too but no sane person actually wants to live in a world full of them. TV is entertainment that does not necesairly mimic reality.