That's how I assumed it was made until I saw the behind-the-scenes video, i.e. a production company makes a generic video that takes several months to complete.

That's how I assumed it was made until I saw the behind-the-scenes video, i.e. a production company makes a generic video that takes several months to complete. They then pitch it to a music label for some up-and-coming artist who is added to the video (using some sort of low frame rate effect in front of a projector or green screen).