Apple makes photo realistic renders of all of its products to use for commercials and reveal trailers. They have for a long time now.

Everything Apple does, hardware and software, is visually realized in a computer first. They take those concepts and CAD drawings and polish them into fully realized CG models that they can do anything with.

Then you get footage of the new iPhone flying through a fountain of liquid metal with realistic collision and particle effects. It would be harder to film a real phone and composite CG into it in post.