I hesitate to fully 'agree' or 'disagree' with anything so I will disagree with your agree/disagree paradigm and say:
I believe Andersen has recognized something that needs absolutely crucial self-reflection upon in our society, but that he doesn't seem to have quite wrestled with the core of why this phenomenon is occurring.
Now that i've established myself with that Dr. Suessian introduction and a really fuckin' wordy thesis, I'll say this. I have no idea what it is to have been born from one of those early eras. Through depictions in television and media it is clear to me the palpable flavor and spirit that seems to come steaming hot off the fashion styles of the past. It seems that in each of these individual decades 20's, 30's, and so on that the energy and character of the times was so intense that it had to pervade and permeate through every facet of culture: Cars, Clothes, Architecture, Music, Literature and the myriad of examples Andersen used, many many of which went straight over my head.
That being said, I don't think Andersen quite knows what it is to have been born within my era, either.
Because for most of my character developing years i have been inundated with culture and history. Every---EVERY country and all its history therein had been connected to each other inside of a decade. INSIDE OF ONE FUCKING DECADE.
The amazing amount of inspiration and tragedy and beauty and culture was suddenly at my doorstep and in school and available via google search. God bless google search.
My point being is that later on in that essay Andersen posits that we may be potentially maxed-out. And that is what I can agree with!
When you're a young man and/or woman and you are trying to express yourself, find words or clothes and poetry or music that can express yourself and you have the entire history of humanity at your fingertips you do tend to get a little derivative.
And finally, the crux of my response:
My generation has lost a sense of we. Each of these eras of the past was filled with a sense of us. Women felt sexually liberated all at once in the 20's. America felt down trodden by an unnecessary war in the 70's. There was generally a sense of movement of the people as one.
But now there are just 7 billion 'i's. The internet has given all of us access to new ways to express who we are.
I.E. At 25, I am not a veteran. I have scarce friends who are veterans. There is a war going on and a massive portion of America and it's families are closely tied to that. Despite being in the same country, the same state and city as many of these people, I related almost zero to their day to day plight. The same could be said for so many aspects of America today. We are all very shattered and our individual experiences have become very specific. We then look to the past for people with whom we can relate, and may style ourselves like them. Find ourselves kindred and akin to them.
While I could delve much further into this and the many contributing factors to this phenomenon there is sadly a word limitation on this response, so I say to Kurt Andersen:
Yes culture has stagnated. We ate too big a meal and however long it takes to digest is how long it takes. But innovation is far from over.