Stack Overflow's Decline Threatens the AI Models It Once Trained

Stack Overflow has seen a sharp drop in question volume since ChatGPT launched in November 2022, leading to a 28% staff layoff in October 2023. Developers increasingly turn to AI tools like ChatGPT and Copilot for direct answers, bypassing the forum that once served as a primary resource. The concern extends beyond Stack Overflow itself: large language models were heavily trained on its high-quality, human-reviewed archive, and that archive is no longer growing at the same pace. Research published in Nature in 2024 by Shumailov and colleagues demonstrated that models trained on AI-generated content degrade over generations, a phenomenon called model collapse. As new human-contributed data dries up, future AI models risk becoming increasingly reliant on stale or synthetic information, potentially reducing their ability to handle novel or niche programming problems.