Evidence since late 2021 shows a mixed picture on severity but clearly contradicts the idea that Omicron was a “nothing burger” that wouldn’t materially worsen the crisis relative to Delta.

On per‑infection severity, multiple large studies (e.g., Kaiser Permanente Southern California, CDC/California analyses) found Omicron infections were substantially less likely than Delta to lead to hospitalization, ICU admission, or death, and were associated with shorter hospital stays. Estimates include ~40–50% lower hospitalization risk and ~70–90% lower risk of death versus Delta, with shorter median length of stay. (kp-scalresearch.org) Some hospital-based cohorts, however, found that once hospitalized, Omicron and Delta patients often required similar levels of intensive care and respiratory support. (hopkinsmedicine.org) So Omicron was not more virulent than Delta; if anything, it was somewhat less virulent.

But Chamath’s stronger claim—that Omicron would not significantly worsen health‑system impact or the overall COVID crisis relative to Delta—is refuted by population-level data:

• CDC COVID‑NET data show that during Omicron predominance (January 2022), weekly adult hospitalization rates in the U.S. peaked at 38.4 per 100,000, exceeding both the prior winter 2020–21 peak (26.1) and the Delta peak (15.5). (pmc.ncbi.nlm.nih.gov)
• A CDC analysis of national trends concluded that the Omicron wave produced the highest numbers of COVID‑19–associated ER visits and hospital admissions since the start of the pandemic, explicitly noting that this surge strained the health‑care system, even though severity per case was lower. (cdc.gov)
• National hospitalization censuses during early January 2022 reached record levels, surpassing the previous U.S. peak from January 2021, with over 132,000–147,000 people hospitalized with COVID‑19 as Omicron spread. (anews.com.tr)
• CDC data comparing peaks show that during the Omicron wave, average daily cases (~799,000) and daily hospital admissions (~21,600) far exceeded the Delta wave’s daily cases (~164,000) and admissions (~12,000), even though deaths at the Omicron peak (~1,850/day) were somewhat lower than at earlier waves. The CDC explicitly warned that the high volume of hospitalizations could strain health systems, despite lower per‑case severity. (upi.com)

In other words:

• Biologically, Omicron was generally less severe than Delta on a per-case basis.
• System-wide, its extreme transmissibility and immune escape drove record case counts and record or near-record hospital burdens, clearly worsening stress on health systems relative to the Delta wave.

Because the prediction bundled both claims—downplaying danger and asserting that Omicron would not materially worsen the COVID‑19 crisis relative to Delta—the overall forecast that it was a “complete … nothing burger” is wrong.