So it's basically saying that the western civilization is the main character of history and whatever else was going on in The Americas, Asia (including West Asia/the Middle East), and Africa was inconsequential.

For one big example of how much it centres western civilization, the dark ages were also roughly when the Islamic Golden Age took place.

But to go even further than that, the Carolingian Renaissance occurred during the dark ages, so it's not even the west or Europe that we're talking about when we call it the dark ages but a fictionalised notion of "western civilization" that goes from Ancient Greece to Ancient Rome to a big gap where "nothing important happens" to the High and Late Middle Ages in Europe where things like the Renaissance take place.

It's also mythologising because it implies that Western Europe are the heirs to the achievements of Ancient Greece and Ancient Rome because they sorta inherited their scientific and technological legacy.

The inconvenient fact that is that the Islamic Golden Age preserved a whole lot of writing and technology from Ancient Greece and Ancient Rome by translating important works, not to mention building on these scientific and technological advances and developing their own, so they would have an equal claim over being heirs to western civilization by that same logic. Also the Islamic Golden Age is essentially how most of the science and technology from Ancient Greece and Rome gets to Western Europe.

But that's uncomfortable for some people to admit, so they just ignore it and tell eachother fairytales about history.