Just as others have remembered I heard the same thing over & over again back in the late 1960's and throughout the 70's. In 1973 everyone was saying this would be the last Assembly in this "Old System of Things" and ever after that everyone kept repeating "things just can't go on much longer". Long after I faded in the early 80's, around 1988 my JW Aunt was still telling me how close the End was and how I needed to attend meetings again. She to is now long dead with no big "A" in sight. What a pipe dream! How sad so many lived such wasted lives for this complete fantasy nonevent.
In the late 1960's and early 70's all this seemed much more real because so many "worldly" experts agreed that there were numerous world-ending problems boiling over all over the Globe and the Watch Tower used quaotes from them to strengthen their arguments. a Cold War ready to explode into full blown "hot" war with Vietnam being one of the ignition points with the potential for Nukes and Germ warfare being used. Polution out of control poisoning everyone, the threat of another Ice Age, crime and violence stats going through the roof, immorality, drugs, fuel shortages, famines, Middle Eastern turmoil, and on and on. The movies from this period also fueled this "End of the World" feeling such as Soilent Green, Omega Man, A Boy And His Dog, Planet of The Apes, just to name a few. There really was a general feeling among JWs and non JWs alike that things were going to Hell in a hand basket because of the social upheaval and general changes society was going through in this period. The music and popular culture celebrated rebellion and the movies and TV shows were darkly obsessed with crime and vice as cities like New York, Chicago, and L.A. had record crime and murder rates with active Red Light districts. Crime dramas quickly replaced the Westerns of the early 60's on TV and movies like Taxi Driver, Dirty Harry, Dog Day Afternoon, Midnight Cowboy, Hard Core, Death Wish, The French Connection, Serpico, The God Father, Walking Tall, Billy Jack, showed the dark underbelly of America.
In short, there was much more external evidence for the Watch Tower bunch to point to back then than today and I can't imagine that it feels as real for the JWs today as it did for us back then. Not to mention the WWII era, if this Hell on Earth wasn't the beginning of Armageddon then nothing else could be. Old Rutherford had lots of evidence for the END during this period and yet it never came. Things look pretty damn hopeful now days compared to these times so I think we are going to be fine. I would guess your average JW today is far more skeptical about the big "A" today than at anytime in the Watchtower Organization's failed predictive history and I'm guessing their stagnant growth is evidence of this lack of enthusiasm for all things Apocolyptic.