I once said "Some people living in 2025 aren't very far advanced from people who lived in the Dark Ages" (or Middle Age, whatever). Then somebody replied "... but they are wearing nice suits!". That's about the difference. The layer of modern civilization is thin.

Wikipedia has some interesting parts about it as well:

The Dark Ages is a term, now deprecated by most historians, for the Early Middle Ages (c. 5th–10th centuries), or occasionally the entire Middle Ages (c. 5th–15th centuries), in Western Europe after the fall of the Western Roman Empire, which characterises it as marked by economic, intellectual, and cultural decline.

The concept of a "Dark Age" as a historiographical periodization originated in the 1330s with the Italian scholar Petrarch, who regarded the post-Roman centuries as "dark" compared to the "light" of classical antiquity.[1][2] The term employs traditional light-versus-darkness imagery to contrast the era's supposed darkness (ignorance and error) with earlier and later periods of light (knowledge and understanding).[

Doesn't seem so far away now does it.