While the monotheist religions had bans on loaning money, Buddhism doesn't. Why didn't bankers manage to consolidate power in China during the Middle Ages?
Until the 20th century, the reason was the "one career" nature of Chinese society. That is, the only honorable career was to take the national examinations to qualify as a member of the government. Passing the district examination made one a member of the local hierarchy. Passing the provincial examination got one a provincial slot, and passing the national examination took one to the capital. Would be bankers wasted their youth studying "philosophy" until they flunked the examinations (most did).
Imagine a society where all the top (merit) scholars and SAT achievers went to work for the government, stripping the "cream of the crop" from the private sector.
With a system like this, the Chinese government went out of its way to destroy, or at least prevent the rise of any alternate source of power. The Chinese fleet was was first immobilized after 1433, then dismantled during the course of the 15th century after the Treasure fleet went outside of East Asia to the Middle East and Africa, according to this source:
"In the following years, official support for the shipyards on the Yangtze >River slowly dried up. No more expeditions were ordered, mirroring the way that >Chinese society was turning in on itself in a conservative mode.
Confucianists in the imperial court saw to it that Zheng's ships were burned after his last voyage and made every effort to systematically destroy all official records of the voyages. The days when a Chinese fleet exploring distant lands under the command of the eunuch Cheng Ho were to fade into an almost forgotten memory.
The Ming navy had 3,500 ships in the early 1400s, but within decades it was a capital offense to build boats with more than two masts. In 1525, the emperor ordered the destruction of all seafaring ships, and the arrest of the merchants who sailed them. By 1551, it was a crime to sail the seas in a ship with more than one mast."
Someone like Germany's Jakob Fugger would have been unheard of in Chinese society: He would have been expropriated (and compensated with a government post) once he got to a certain level.