Preventing any kind of dynamic agency from growing on the web is one of the most severe threats to user-agency I can imagine. It's a direct strike at one of the most core distinctions that makes the web different from everything else. I really believe strongly that the web will advance once we start making more adaptive scripts/extensions, scripts that can gain & accrue capabilities, and this directly prevents advance.

V2 extensions are no longer allowed but there's still no progress or path for Tampermonkey to even experiment with.