I’m not so sure about that one. The Roman Empire had already disintegrated before Islam was even really getting started and Europe was falling into a fragmentation of fiefdoms and unsafe travel.
I’m sure the invading hordes of islam didn’t help, but I think the dark ages was dark for many reasons.
The history that the Roman Empire fell when the German barbarians invaded Rome is false. What the Germans did was take over the Roman Empire and keep it running the way it was when they took over. They retained classical culture. They spoke Roman. They hired Roman philosophers, and Roman attorneys to teach their children and run their schools. It became the Bysantine Empire that was still the classical empire. However, before Islam invaded, the Bysantine empire had been weakened by the war with Persia and the Black Plague.
The Black Plague had caused the Bysantine Empire to lose 1/3 of its population and its economy had collapsed by 2/3rds.
Meanwhile the Islamic caliphs, controlled by family members of Mohammad began their conquests and were slaughtering Christians and Persians by the thousands. There was massive destruction, including the destruction of Egypt’s network of Roman viaducts that created the greatest food production center the world had ever seen. Egypt’s bread basket was gone! Syria was the intellectual center of the classical empire in the world—gone! In 25 years the classical world lost its ability to feed itself and its intellectual brain trust.
By 750 A.D. from Pakistan through Afghanistan, Turkey, Iran, Saudi Arabia, Jordan, Egypt, Libya, Tunisia, Algeria, Morocco, and Spain was Muslim. Before, much was Christian through the ministry of the Apostles. Islam fought 548 battles against the classical world of Europe. Many were slave raids but they were no less slaughters in ways unimaginable. Chopped heads were thrown on piles 15 feet high. Women were raped in the blood of their slaughtered husbands—Mohammad style! It was this conquest of the classical world that caused the Dark Ages.