American Bank CEO Brian Moynihan recently issued a noteworthy warning. During the earnings call, he was frank—if stablecoin issuers are allowed to pay interest, these products could drain up to $6 trillion in deposits from the US banking system.

How big is this number? Imagine the entire US banking system's deposit pool, and the transfer of $6 trillion—consider the consequences.

Moynihan cited research from the US Treasury Department indicating that once paying interest on stablecoins becomes a reality, large-scale movement of bank deposits into stablecoins is entirely possible. The operational logic of these stablecoin products is actually more similar to money market funds—funds are stored in cash, central bank reserves, or short-term government bonds, rather than being used for lending.

The question is: what happens if bank deposits decrease? The direct consequence is a reduction in the funds available for banks to lend. Who is most affected? The answer is small and medium-sized enterprises that mainly rely on bank loans. They cannot easily raise capital from the capital markets like large corporations, and tighter bank lending means increased difficulty and higher costs for financing. The overall borrowing costs in the economy could therefore rise.

The underlying logic is quite clear: if stablecoins truly offer interest income, they become a more attractive option for depositors than traditional bank deposits. But this flow could disrupt the balance of the existing financial system.