Open-source RVC ships as a Python web app. For a film dubbing pipeline that's a workflow break: stop the DAW session, export audio, open browser, upload, generate, download, re-import, re-sync. Frame-accuracy, automation, undo history - all lost in the round-trip. Native plugins are how serious audio tools live - inside the session, on the track, rendered to the timeline. The gap between "powerful AI model" and "tool a film audio team can actually use" was a plugin.