Acording to this historian it was pretty awful: https://www.amazon.com/Fall-Rome-End-Civilization/dp/0192807...

"The book recaptures the drama and violence of the last days of the Roman world, and reminds us of the very real terrors of barbarian occupation. Equally important, Ward-Perkins contends that a key problem with the new way of looking at the end of the ancient world is that all difficulty and awkwardness is smoothed out into a steady and positive transformation of society. Nothing ever goes badly wrong in this vision of the past. The evidence shows otherwise."

We've seen how this looks like in modern times with the fall and decline of the Soviet Union. The US could end up similarly in the future: invading countries under flimsy pretexts, assassinating opponents, politics utterly corrupted by money, trying to bully other countries into submission, etc.

For an opposite perspective, Bryan Ward-Perkins' "The Fall Of Rome: And the End of Civilization" is a readable-by-the-layperson argument that the end of Roman authority in Western Europe resulted in significant falls in trade, health, literacy, cultural achievement, and more: https://www.amazon.com/Fall-Rome-End-Civilization/dp/0192807...

There's been a lot of recent interest in this topic. For example: http://www.amazon.com/The-Fall-Rome-And-Civilization/dp/0192...

Summary is that though Rome didn't fall overnight, there was a massive economic collapse first in the west and then several centuries later in the east (the latter coming on the heals of a devastating outbreak of the plague).