If the Middle-East wasn't Muslim or Arab

Almost every single Arab nation wasn't actually arab until the 11th-12th century (a few centuries after the muslim conquest), even though civilization had existed there for over 4000 years at the time. If the Arab-Muslims hadn't invaded and made Arabic and Islam the cultural pillars of the region, would the Middle-East have been a better place?

Judaism and Monophysite Christianity is adopted slowly by most Arabs, Levantines, and Egyptians (With North Africa taking on whatever Christian faiths were found there). Any ambitious Arab State (Ghassanids or Lakhmids like) might choose to adopt Monophysite Christianity much like the Khazar Khanate chose Judaism: As a means of being able to play to both Byzantine (Orthodox hated the Monophysites but still could get along with them - this isn't really true for Nestorians, which I think Lakhmids were?) and Sassanid politics.

Central Asia would have remained a more religiously divided landscape between Buddhists, Eastern Christians and some of those small sects/cults whose names elude me (Gnostics, Manichaeism). Persian and Iran would remain the cultural and political center of the Middle East at least until the arrival of the Turks.

I don't know much detail about the Gnostics, but it's quite possible that they would have been the most successful contender to Christianity. Zoroastrianism as I understand it was an elitist faith of the aristocracy and priesthood in Iran, with the populace being Christian, Jewish, Gnostic, or various other faiths.

The Pan-Islamic world that encompasses much of Africa, West/Central/South/South-East Asia wouldn't I think have had any sort of repeat without a faith like Islam. You would have seen Christianity dominating Africa, contending with Gnosticism in Western Asia, Gnosticism and Buddhism in Central Asia, and an unchallenged Hinduism in South (east) asia.

With a point of divergence so far back, it'd be tough to account for all of the potential events due to the butterfly effect. It'd be interesting if someone worked on a detailed timeline of a world where Islam never existed or never took off.