Actually we have a decentralized Bank and in my opinion it is DeFi, a DeFi platform, all crypto users can do buying and selling, lending and borrowing.
All aim to speed up the transaction process, but some of these platforms must be trusted and not end up with fraud, I mean the team and developers have official permission to prevent the loss of investors' money due to fraud on these platforms.
Traditional banks until now are worried about the existence of crypro, because banks do not have the technology as good as crypto.