Vaccine timing: Chamath said a COVID-19 vaccine was “at best 18 to 24 months” away from April 2020, implying no widely available vaccine before roughly October 2021.

• In reality, the Pfizer–BioNTech vaccine received FDA Emergency Use Authorization on December 11, 2020, and the U.S. vaccination program began immediately thereafter. (ama-assn.org)
• U.S. eligibility expanded rapidly; by April 19, 2021, all states had opened vaccination to all adults 18+, meaning vaccines were widely available to the general adult population about 12 months after his April 2020 statement, not 18–24 months. (cdc.gov)

Economic and social recovery: He also said that without a vaccine, the U.S. would “never get to 100% of where we were before” and that the next two years would involve “a tremendous amount of difficulty.” The U.S. did experience severe disruption through 2020–2022 (Delta and Omicron waves, uneven sectoral recovery), but key economic indicators recovered earlier than his framing suggests:

• U.S. real GDP returned to and then exceeded its pre‑pandemic (Q4 2019) level by Q1–Q2 2021, well before spring 2022. (presidency.ucsb.edu)
• Many states substantially lifted capacity limits and other business restrictions during spring–summer 2021, long before his implied two‑year horizon. (hr.dickinson-wright.com)

While his qualitative warning that the following two years would be very difficult was broadly true, the testable, quantitative core of the prediction—no widely available vaccine for 18–24 months—was clearly too pessimistic by roughly 6–12 months. On balance, that makes the prediction wrong overall.