Python isn't a side project to yolo on. Updating the GC without a PEP caused massive issues for actual people using Python. If you want to impact software used by millions of developers then you better be willing to handle a bit of process.

They're not being asked to halt development, they're being asked to halt landing new features on the cPython main branch.

The JIT project already lost a lot of momentum when the people working on it lost their jobs (at Microsoft)..