There is plenty of evidence for the "decline and fall" camp but notably that conclusion varies a lot based on geography and perspective. Relying on mostly archa

There is plenty of evidence for the "decline and fall" camp but notably that conclusion varies a lot based on geography and perspective. Relying on mostly archaeological evidence, we do indeed see substantial drops in urbanization and economic output in the 5th and 6th centuries across the Western Empire which surely would have made life significantly, tangibly worse for a lot of people. But that decline happened at very different rates in different places, such that a 5th century Roman in North Africa might have experienced a slow transition whereas their peer in Britain might have experienced a near-total collapse. From a political perspective, many of the successor states in places like Italy continued to rule in a distinctly Roman fashion, using Roman norms, Roman laws, and Roman institutions - in other words, yes, a "'transition' between political org charts." These states were certainly weaker and poorer, but the wealth and capabilities of the Western Empire itself had been shriveling for a century by the time 476 rolled around. The continued expansion of the Church also made up for some of this decline in state administrative capacity among the successors. From a cultural perspective, your point about the sophistication of literary output is flat-out incorrect. And we haven't even mentioned the Eastern Empire - which was always the richer half to begin with, and actually experienced a number of later periods of resurgence and growth. So the actual evidence is much more nuanced, and neither of your conclusions ("an absolutely miserable period of history", "Gibbon's history of the era is masterful") are sustained by any modern scholarship.