I believe the Turkic people came before the Mongols and they took power because middle easterners had that terrible idea of relying on military slaves or otherwise foreigners.
Saladin's army, for example, was composed mostly of Turks.
That stuff goes back to Carthage and their mercenary armies. It seems that the Middle East hydraulic empires had a very urbane, very peaceful (domesticated) civil society. With the exception of the Bedouins. Europe, in contrast, had a large rural population that acted as cannon fodder.
It makes sense you do not want to arm people living in crowded cities.
FWIW, many scholars of China believe the Qing Manchus were one of the reasons China trailed behind the West. These nomads didn't care as much about science and technology as the Han Chinese. Being nomads and few in numbers they also didn't care too much about arming a powerful infantry composed mostly of Hans. They preferred to keep an elite of cavalry that could travel fast and quash rebellions. That obviously didn't work when Europeans and later on the Japanese attacked them with modern weaponry.