For 150 years before the era of Timur, the steppe-Mongols owned Central Asia and Iran. But under Timur the rulers of Central Asia became stronger than the steppe khans. Why did it happen?
A capitalist economy developed between Genghis Khan and Timur in the cities of Central Asia along the Great Silk Road. The steppe inhabitants converted to Islam and became fellow believers of the townspeople. Now city rulers like Timur could easily recruit steppe warriors to their armies, which was impossible in the era of Genghis Khan.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.