There is a logical explanation for this.
First, the volatility inherent in digital assets. The fact is that the main goal of every bank is to make a profit. The slightest fluctuation in the cryptocurrency market increases the risk of reducing all projected profits to zero. Today, cryptocurrency is showing a certain stability, but even despite these indicators, most financial institutions still prefer to provide traditional banking services for corporate clients, whose activities they understand.

Decentralized Cryptocurrency is not controlled or limited by anyone alone, there is no single administrator and regulator. Not a single financial, tax, government organization can influence the actions of participants in the payment system.
Ethereum is a multifunctional virtual platform on which blockchain-based applications (online services) are created. Applications work as "smart contracts (smart contracts)" that exclude third parties (intermediaries) in the transaction process. On their basis, it is possible to create a platform that will stimulate banks to lend against the security of cryptocurrency without fear of losses, and this, in turn, will interest the financial sector to place its assets in cryptocurrency?

In solving this problem, I took as an example the existing US financial system.
Assuming that Ethereum is the Dollar, and the smart contract is the Office of the Comptroller of the Currency of the United States (OCC), and ETH-WORLD tokens are the Securities of the US Treasury, we get a financial model of a new decentralized economic system based on cryptocurrency. I implemented all this in my project, in contrast to the existing Fiat, it completely lacks an external emission regulator and is managed by the smart contract program.
http://prosh.info/smart_eng.html