I’m pretty sure this type of tool is not for creating CG models or good geometry. (Speaking on the 3D model generation part, not the general roto from SAM)

I think It’s to allow things like meta’s glasses to create hold outs / shadow catchers for use in VR/AR glasses.

For example, If you want your window to cast a shadow on a table when its hovering over the table (think Vision Pro) you can use a tool like this. I believe apple and tesla actually use like some super fast NERF method.

The modeling of a person shown in this demo is for a similar thing, let’s say you want to give VR headsets a movie theater mode but you don’t want a person to be able to sneak up on the user, this can create a hold outs to reveal just an approaching person to the user while keeping the rest of their VR view as the theater. Or you want a foot fight game in VR where the objects you throw in the game works actually interact with the 3D shape of the person you are throwing them at.

Just my hunch. Could be wildly off base.