Our civilization is unique in certain respects
All civilizations are unique in certain respects, while sharing traits in others. The similarities are the bigger part of what I'm discussing as for the most part human nature does not change.
notably continual technological/scientific advance
While it's incorrect to assume that, I'm glad you mentioned it, because the funny thing about Dark Ages is that there is an advance in certain material factors within these periods in every case that i've studied, often significantly. The Dark Age in the end of the Near East/Middle East/Mediterranean Bronze Age saw the rise of the Iron Age in tools and weapons, but the near total collapse of civilization everywhere except Egypt, including the use of writing in Greece. It lasted some 400 years.
The European Dark Ages after the fall of the West Roman Empire and the rise of Islam saw an incredible growth in some areas of technical progress, including the moldboard plow and the invention of the modern clock, etc... But also, there was a significant decline in other technical and scientific respects.
What does collapse during a Dark Age in every case are the political structures and institutions, spiritual and cultural values and morality, and a rise in endemic and savage warfare, revolutions, raiding, criminal activity, and a state of flux between absolute tyranny and absolute anarchy without much solidity in between. There is often extreme want and destitution and also extreme wealth, even within the same societies. Palace coups and conspiracies, bizarre sects and secret societies are commonplace during these times...
Of course, just like a fish in the ocean does not see water, a person raised in such a period entirely often does not see that this is a Dark Age or collapse period
, so I don't think it will share the fate of previous ones.
Often said. There's a reason though that Spengler called it the ''Faustian'' Civilization, as there has been a deal with the Devil made. And so when it is falling, the slide to rock bottom will likely be more profound than that of previous civilizations.
:?: After Napoleon, Western civilization was on the threshold of unprecedented material and scientific progress, quite unlike a dark age.
See above about ''unprecedented material and scientific progress''. I understand that that is also the metric by which you personally measure things so there is that, but all I can say to that is to ''look ahead''. It'll reach you, the Collapse, you'll know it.
As for Napoleon, he was a Condotierre, an Adventurer. The very fact that he rampaged across Europe for over a decade, after the cataclysms of the American and French Revolutions, is pretty compelling proof of the things i'm talking about.
But man is a fickle and disreputable creature and perhaps, like a chess-player, is interested in the process of attaining his goal rather than the goal itself.