Another comment pointed out that these were made by the Jam Handy Organization[0].
Just hypothesizing, but either GM might distribute these and have showings for staff as part of training. Almost certainly not for the engineers that already learned this but perhaps sales staff so they could better explain the mechanism and benefits to buyers.
I believe Chevy contracted his production company for dealers' training material. Notably, he produced the "Hired!" films for dealership salesmen, one of which was riffed by MST3K in their "Manos: Hands of Fate" episode
To me it looks like it's aimed at consumers, from the part at the end. It's as if the movie is intended to overcome worries "but is all this complexity really safe?" by showing how you can load the differential with running people without issue.
Just hypothesizing, but either GM might distribute these and have showings for staff as part of training. Almost certainly not for the engineers that already learned this but perhaps sales staff so they could better explain the mechanism and benefits to buyers.
[0] https://en.m.wikipedia.org/wiki/Jam_Handy