The film was shot almost entirely in Unity, then the final render used some extra stuff and other tools. But the scenes, shots, etc were done in Unity. A quick google shows you this.
That article I seems to imply Unity only used to generate "camerawork" data (camera positions and movements), and the actual rendering is done on other system using that camerawork data. IIRC on 2019 (Lion King release year) Unity didn't even have ray tracing support yet, so I think the final render might not use Unity at all, but Unity editor itself used extensively during production.
In contrast, Unreal Engine rendered scenes seems to be used in actual footages on some recent shows. Was Unity acquisitions of CGI firms meant to pursue this direction, or boost Unity editor usage during firm production like in Lion King?
You are correct, they used it for production, building the scenes, getting camera data. I then assume they exported the scenes and camera data to whatever they used for the final render. So Unity was used for 70-80% of the work.
It is possible but I don't know. Just was trying to point out that it's more than just some demo that it was used for.
