The end of the zero-interest-rate period compressed lending margins, but it had a silver lining. It forced fintech companies to become 'full-stack' by acquiring bank charters and building significant revenue streams from customer deposits, ultimately making their business models more durable.

The common annoyance of banks not paying interest on checking accounts stems from history. Regulators once prohibited it to ensure bank stability. After the rule was repealed, the interest-free float had become such a large and reliable profit center that banks became structurally reliant on it.

Quantitative Easing (QE) forced massive, often uninsured deposits onto bank balance sheets when loan demand was weak. These deposits were highly rate-sensitive. When the Fed began raising rates, this "hot money" quickly fled the system, contributing to the banking volatility seen in March 2023.

The recent uptick in the Fed funds rate was not a direct signal of scarce bank reserves. Instead, it was driven by its primary lenders, Federal Home Loan Banks, shifting their cash to the higher-yielding repo market. This supply-side shift forced borrowers in the Fed funds market to pay more.

Banks oppose stablecoins because they disrupt a core profit center: the spread between low interest paid on deposits and high yields earned from investing those deposits in treasuries. Stablecoins can pass these yields directly to consumers, creating a competitive market.

Contrary to the belief that high rates boost revenue from reserves, Circle's CEO reveals lower rates fuel stablecoin adoption. High rates increase the opportunity cost of holding non-interest-bearing cash, whereas lower rates encourage capital velocity and investment in new technologies, expanding the market.

Consumers are largely insensitive to the interest rates they are charged, rarely seeking out cheaper options like credit union cards. This behavioral pattern means that cutting rates is an ineffective customer acquisition strategy. Instead, issuers invest heavily in marketing, which proves more effective at attracting new borrowers.

Modern Western economies are dominated by services (media, law, medicine) that are not capital-intensive and don't rely heavily on borrowing. This diminishes the impact of interest rate changes on the real economy, explaining why aggressive rate hikes haven't caused a recession and why low rates post-2008 didn't create inflation.

While AI and fintech lower switching costs for retail customers, small and mid-cap banks retain their core clients—small to medium-sized businesses. These businesses depend on the sticky, lifeblood credit relationships with their local banks, making them less likely to switch for better deposit rates.