The "dark ages" is a good description of what happened throughout most of Western Europe after the fall of the Western Roman Empire. The nuance is that the Eastern Roman (Byzantine) Empire survived much longer, and that somewhat well organized kingdoms remained in parts of the West for a time.
But there was a remarkable economic and cultural collapse in most of the former Western Roman Empire. Large cities mostly disappeared. Literacy nearly disappeared, and was only really preserved by the Church. The extensive Roman system of taxation and the public goods it paid for (roads, aqueducts, baths, theaters, security) nearly disappeared. Without large cities, roads and security, long-distance trade collapsed and the economy became much simpler. Skilled trades that existed in the highly complex Roman economy were forgotten. Classical literature and philosophy were largely lost in the West. Essentially, urbanized classical civilization disappeared.
There's a tendency to talk nowadays about the "transformation of the Roman Empire," rather than its fall, but I find that a bit too euphemistic.
> Large cities mostly disappeared. Literacy nearly disappeared, and was only really preserved by the Church.
Neither of those were wide-spread in Western Europe during the Roman empire either. If you take a look at the major cities of the Roman Empire they're generally in either Italy, Byzantium, or North Africa[0]. All of which continued past the fall of Rome. Literacy rates were also questionable [1].
> Without large cities, roads and security, long-distance trade collapsed and the economy became much simpler.
Long-distance trade certainly did not collapse after the fall. While it did decrease to certain extent in the near time period, it rebound within a century or two [2].
> Neither of those were wide-spread in Western Europe during the Roman empire either.
Literacy was much more widespread in the Roman Empire than during the Dark Ages. If you go to archaeological sites like Vindolanda, you can see letters written by fairly ordinary people to one another. There was an entire literate culture that disappeared. The reason why they're called the "Dark Ages" in the first place is because of the paucity of written records.
> If you take a look at the major cities of the Roman Empire they're generally in either Italy, Byzantium, or North Africa
First of all, Italy and North Africa were part of the Western Roman Empire. Italy fared better than Gaul and Britain until the mid-6th Century, but Rome eventually declined from several hundred thousand inhabitants in the late Empire to a few tens of thousands.
There were major cities in Gaul, the German provinces and Britain, though: Augusta Treverorum, Londinium, Lugdunum, Narbo and Rheims all had tens of thousands of inhabitants during the Empire, but during the Dark Age shrank to a small fraction of their former size.
> Long-distance trade certainly did not collapse after the fall. While it did decrease to certain extent in the near time period, it rebound within a century or two [2].
The source you cite only notes that trade "never ceased." That doesn't mean there wasn't a massive collapse. The article notes that trade continued to decline for centuries after the fall of the Empire, into the 9th Century AD. The economy of Western Europe probably did not reach a similar level of development as in the Empire until the High Middle Ages.
What I'm pointing out is that the magnitude of the declines in literacy, trade, urbanization, etc. in most of the former Western Roman Empire were striking, and that they really can be characterized as a "collapse."
But there was a remarkable economic and cultural collapse in most of the former Western Roman Empire. Large cities mostly disappeared. Literacy nearly disappeared, and was only really preserved by the Church. The extensive Roman system of taxation and the public goods it paid for (roads, aqueducts, baths, theaters, security) nearly disappeared. Without large cities, roads and security, long-distance trade collapsed and the economy became much simpler. Skilled trades that existed in the highly complex Roman economy were forgotten. Classical literature and philosophy were largely lost in the West. Essentially, urbanized classical civilization disappeared.
There's a tendency to talk nowadays about the "transformation of the Roman Empire," rather than its fall, but I find that a bit too euphemistic.