@mgorny TBH the discussion doesn't seem bad to me. They don't say "fuck off", just ask a few questions. I've seen discussions way worse, especially in PyCQA and PyPA projects where dramas are a daily routine.
FOSS maintainers live in a different world. Our "current" #python version is 3.8. The 3.10 version reaches EoL in Ocy 2026, and that's when we'll be able to unconditionally use ExceptionGroup. So, yeah, we're careful about using anything that isn't in 3.8 🙃