Evidence since March 2023 runs opposite to the prediction that central banks would "take on the whole balance sheet" and function as one giant primary bank for the economy.

1. U.S.: emergency backstops were temporary and are being unwound, not expanded into a permanent mega‑bank.

   • The Fed’s Bank Term Funding Program (BTFP), created in March 2023 after the regional‑bank stress, was explicitly temporary and stopped making new loans on March 11, 2024. (en.wikipedia.org)
   • The Federal Reserve has been shrinking its own balance sheet via quantitative tightening: total assets fell from about $7.1T (Sept 25, 2024) to about $6.7T (Mar 26, 2025). (federalreserve.gov)
     These moves reduce, rather than expand, the share of the financial system’s assets held or directly backstopped on the Fed’s own balance sheet.

2. Private banks still dominate balance sheets; there is no de facto “single bank.”

   • As of early 2025 there are roughly 3,900–4,500 FDIC‑insured commercial banks in the U.S., with about $24.5 trillion in assets. (statista.com)
   • By contrast, the Fed’s balance sheet is about $6.7 trillion, and consists largely of Treasury and MBS holdings, not the direct assumption of commercial‑bank loan books. (federalreserve.gov)
     The structure of the system is still many private banks funded by deposits and wholesale markets, with a central bank as lender of last resort—not one giant operational bank providing most credit directly.

3. Deposit guarantees have not been turned into a blanket, permanent backstop of all deposits.

   • The standard FDIC insurance limit remains $250,000 per depositor, per bank, per ownership category, even after rule changes in 2024 that mainly simplified trust‑account treatment. (fdic.gov)
   • After Silicon Valley Bank and Signature Bank failed, uninsured deposits were protected via one‑off “systemic risk” exceptions, but the FDIC later recommended keeping the general $250k limit and only considering targeted higher coverage for certain business accounts, which has not been implemented system‑wide. (forbes.com)
     That is not equivalent to central banks or deposit insurers permanently absorbing “the whole balance sheet” of the banking system.

4. Globally, major central banks are also normalizing and shrinking their balance sheets.

   • The ECB has been reducing its balance sheet since 2022 by letting TLTRO bank loans mature and winding down APP/PEPP bond holdings; its consolidated balance sheet fell to about €6.42T in 2024 and is projected to keep shrinking through 2027. (eligher.zentral-bank.eu)
   • The Bank of England is likewise running quantitative tightening, actively selling or allowing gilts to mature so that its balance sheet declines from pandemic‑era peaks. (reuters.com)
     These trends mean central banks are reducing their footprint relative to the banking system, not absorbing a “very large share” of its assets.

Given that (a) the number and role of private banks remain substantial, (b) central‑bank balance sheets are shrinking rather than expanding to encompass most bank assets, and (c) deposit insurance and backstops have not been turned into a universal, permanent guarantee of essentially all bank liabilities, the world today does not resemble a system where “one big central bank” effectively runs the bulk of banking activity. The observable trajectory since 2023 is the opposite of the predicted consolidation of balance sheets into the central bank. Therefore, as of November 30, 2025, this prediction is best classified as wrong rather than merely “too early” or “ambiguous.”