Interpretation of the prediction

The normalized prediction treats the “risk‑free rate” as a real (inflation‑adjusted) short‑term U.S. government yield, e.g., TIPS or nominal Treasuries minus inflation. The claim was that after September 2020 these real risk‑free rates would soon become negative and stay below zero for a sustained period.

What actually happened

1. TIPS real yields were negative for an extended stretch after 2020.

   • A recap of 2021 TIPS performance shows that by the end of 2021, real yields on 5‑, 10‑, and 30‑year TIPS were all firmly negative (e.g., 5‑year TIPS at about –1.6% real yield on 12/31/2021). (tipswatch.com)
   • Schwab’s analysis notes that from March 2020 through the end of April 2022, most TIPS yields were negative, meaning investors were locking in negative real yields over that entire period. (schwabassetmanagement.com)
   • This implies a roughly two‑year span (2020–2022) of broadly negative real risk‑free yields, squarely within the “next few years” after September 2020.

2. Short‑term real rates derived from nominal Treasuries were also deeply negative.

   • At the end of 2021, 4‑week Treasury bills yielded around 0.01% nominal, i.e., essentially zero. (tipswatch.com)
   • Over the same period, U.S. CPI inflation was running in the mid‑single to high‑single digits, so the ex‑post real return on Treasury bills was strongly negative (nominal ≈0% minus inflation ≫0%). This is exactly the textbook definition of a negative real interest rate. (en.wikipedia.org)

3. Consensus commentary acknowledges that real Treasury yields were negative “for quite a while.”

   • Investment and market commentaries from 2022–2023 repeatedly describe real Treasury yields as having been negative across most maturities in 2020–2021 and into early 2022, before turning positive as the Fed hiked rates. (wisdomtree.com)

Assessment vs. the prediction

• Timing (“soon”): Real TIPS yields were already negative around the time of the September 2020 podcast, and remained negative across most of the curve into at least April 2022—well within “the next few years.” (schwabassetmanagement.com)
• Level (“will be negative”): Both market‑observable real yields (TIPS) and ex‑post real yields on short Treasuries were clearly below zero for an extended period. (tipswatch.com)
• Duration (“sustained period”): Roughly two years of broadly negative real risk‑free rates qualifies as a sustained period by any reasonable interpretation.

Nominal policy rates never went meaningfully below zero, but under the normalized interpretation (real risk‑free rates), Chamath’s claim that the risk‑free rate would be negative and stay there for a while is borne out by the data.

Conclusion: The prediction about real risk‑free rates becoming and remaining negative for a sustained period after September 2020 is right.