Looking a bit further into it, a bug report on the GZDoom GitHub page titled “Project management” was opened that gave a little more detail noting issues with the lead of GZDoom pushing untested code, using an LLM to write code and hiding “not insignificant changes in commits, which has people worried that you’ll randomly rip out features that they rely on”. In reply, the project lead simply said “Feel free to fork the project under a” (yes, that really all they said).
A later comment before the bug report was locked points out the specific change in GZDoom that was made with ChatGPT.

Lately it feels like GenAI is gonna push FOSS projects and its maintainers to the breaking point. So much for this great future every AI vendor promised us 🙄