Islam wasn't really advancing as Rome was falling. An oxymoron. Islamic Renaissance happened after the fall of Constaninople? As the Ottomans Empire emerged. It also invaded Rome.

Otherwise it was subjected to crusades and barbarians

Arabs, prior Carthagians were another pillar of Roman demise invading in 846. Moors spread across the common trade route, it is as old as Atlantis, into Southern Spain. Same as they did in the Punic Wars. While barbarians threatened its outer influence. Vikings, Huns. Until it re-established itself in Constantinople. Immediately fighting Islam, Crusades. Didn't a Holy Roman Emperor prior, also invade destroying Alexandria again, like Caesar, the library. Mongols sacked Bhagdad one of the most brutal slaughters in history millions killed.

About these horselords old Hungarian script has understood Aborigines? The phonetics are otherwise global. It even was able to communicate in Swahili. Modern Hungarian is the Latin.

Of course this is subject to debate. But hell. There is a lot that doesn't fit the concentric narratives.

Although he is wrong in concluding Islam was emerging then. It fought Rome for status and then dominated through the Ottomans for centuries. As Europeans fought each other much like Arabs also did but who is counting.