The prediction was that, from mid‑2021 onward, essentially all unvaccinated people would eventually be infected with the COVID‑19 Delta variant.

Evidence from seroprevalence and variant‑specific surveillance indicates:

• By late 2021 and early 2022, Delta did become the dominant variant globally for a time and infected a large share of unvaccinated people, but not all. Estimates from multiple countries show substantial, but far from universal, infection or seroprevalence levels before Omicron arrived (often well below 100%, even when including both vaccinated and unvaccinated populations), leaving many people still uninfected by Delta when Omicron began to outcompete it.
• Omicron (and its sublineages) rapidly displaced Delta in late 2021 and 2022, becoming the overwhelmingly dominant variant worldwide. This means that many people who avoided infection during the Delta wave but were later infected, were infected with Omicron or later variants rather than Delta.
• There is no credible epidemiological evidence that nearly all unvaccinated individuals (let alone literally all) were ever infected with Delta specifically; instead, data consistently show a mix of: people infected with pre‑Delta strains, people infected with Delta, people infected only with Omicron or later variants, and some who (as of 2025) still show no evidence of infection.

Because the statement is strong and specific to the Delta variant ("if you're not vaccinated, you're going to get the delta variant"), and available data show large numbers of unvaccinated people who either remained uninfected through the Delta period or were first infected by later variants, the prediction is best classified as wrong.