What's the point of enlarging the screen into a room? In the 1979 Put That There demo, the user at least used his hand to point things. The model is impressive

What's the point of enlarging the screen into a room? In the 1979 Put That There demo, the user at least used his hand to point things. The model is impressive but the demo felt like a step back. Original demo (fun ending) https://www.youtube.com/watch?v=RyBEUyEtxQo https://www.youtube.com/watch?v=RyBEUyEtxQo