Evidence since late 2021 indicates this prediction was essentially borne out, especially with the emergence and global spread of the Omicron lineage.

Key points:

1. A substantially more immune‑evasive variant did emerge after July 2021.

   • Omicron (B.1.1.529), first reported in November 2021, showed markedly higher ability to evade neutralizing antibodies from vaccination and prior infection compared with earlier variants like Alpha and Delta. Multiple lab studies reported large drops in neutralization titers against Omicron for sera from people who had completed primary vaccine series (e.g., 20–40‑fold reductions compared with ancestral virus).

2. Real‑world data showed much higher rates of infection among vaccinated people than with prior variants.

   • During Omicron waves, countries with high vaccination coverage (e.g., the UK, Israel, the U.S.) reported:
     • Large numbers of breakthrough infections in fully vaccinated individuals, far beyond what was seen with Alpha or early Delta.
     • Rapid declines in protection against infection and symptomatic disease a few months after primary vaccination, with two doses sometimes offering only modest and short‑lived protection against Omicron infection (though protection against severe disease, hospitalization, and death remained substantially higher than in unvaccinated people, especially with boosting).
   • Health agencies and observational studies consistently documented that Omicron caused a much larger share of cases among vaccinated people than previous variants had, largely due to immune escape plus waning immunity.

3. This goes beyond the "partial reductions" in vaccine effectiveness seen by mid‑2021.

   • By July 2021, concerns about "breakthrough" were mostly about:
     • Modest drops in effectiveness against infection with Alpha/Delta compared with the ancestral strain.
     • Some breakthrough cases, but vaccines still preventing most infections in vaccinated populations.
   • With Omicron and its subvariants, many public‑health summaries explicitly characterized it as highly immune‑evasive, noting that prior vaccination or infection was much less effective at blocking infection, even though it still greatly reduced the risk of severe outcomes. This is qualitatively closer to what the predictor labeled a future “true breakthrough variant.”

4. Does this match the normalized prediction?

   • The claim was: after July 2021, a SARS‑CoV‑2 variant will emerge that constitutes a true breakthrough variant—significantly evading existing vaccine protection beyond the partial reductions then observed, leading to substantially more infections among vaccinated people.
   • Omicron clearly:
     • Emerged after July 2021.
     • Showed substantially greater immune escape than Alpha/Delta.
     • Produced waves with many more infections among vaccinated people than earlier variants, even while vaccines (especially with boosters) still protected fairly well against severe disease.

Because the core of the prediction—a meaningfully more vaccine‑evading SARS‑CoV‑2 variant causing many more breakthrough infections—did happen with Omicron and its descendants, the prediction should be judged right in substance, even though vaccines continued to work well against severe disease and were not rendered useless.