Yet for some reason, the Muslim empire went on for a few more centuries................Hmmmmm.
What is your point? Are you suggesting that the Islamic world remained an open, tolerant society that valued scholarship through the middle ages?
The muslims did a great thing when they copied the works of Aristotle (especially Aristotle) and other greek minds into arabic, preserving them. And their own great scholars like Averroes in the 12th century provided medieval christian scholars like Albert the Great and Thomas Aquinas key ideas in their works which led to the scholastic system and formed the basis of Western intellectual knowledge and study for centuries to come.
But by then the Muslims had already rejected anything that wasn't in the Koran. Indeed by the end of his life Averroes himself saw his own works burned in front of him and was forced into exile.
So yeah, Islam had a good run where they merged extreme militarism and scholarship for some 500 years. Good for them. All that ended 800 years ago.