What is this effect called? Is it film-grain?

This looks very much like monochrome Gaussian (as opposed to Uniform, which it’s not) noise at a low opacity. If I were going to reproduce the effect, I’d do this:

• Add the noise to a white layer in Multiply or Darken mode @ about 20% opacity above the object. (The example below is in Darken mode at 21%.)

• Use Photoshop’s Blend If function (in the Blending Options dialog) to allow the whitest parts of the underlying object to show through.

• Scale up the noise layer. Scaling it up makes noise “grain” edges less sharp and gives that “blobby” look.