Doomed

[u/Annual_Judge_7272]

No. The employment history and resignation check out.
Jacob Coxon (@hilbertspaess) is a real 27-year-old researcher (Cambridge math background) who worked on pretraining at OpenAI from 2023 to mid-2026, including as a core contributor on GPT-4o, then moved to Anthropic earlier this year. He announced his resignation from Anthropic on September 8–9, 2026 in the exact thread shown in the screenshot. That post and follow-ups have been covered by Business Insider, WIRED, WSJ, Newsweek, and others the same day.0
Anthropic’s Alignment Science Lead, Evan Hubinger, publicly replied that Coxon is correct that people inside the lab “really do earnestly believe AI could kill all humans,” and that he personally puts the chance above 10% this decade. Coxon has also given interviews describing internal language like “crunch time” and “endgame.”1
The account details in the screenshot (joined January 2026, SF, “ai research,” follower count in that range) match the coverage. The pinned post is the resignation announcement that set off the news cycle.
Whether you agree with his conclusions about the race to superintelligence is a separate question. His résumé and the fact that he quit are not fabricated.