AFAIK, a lot of commercials, particularly for cars, haven’t really shot the physical product in decades and instead used CGI. I think Ikea also makes heavy use of renderings. It’s all kind of insane. OTOH, a hundred years ago ads all used illustrations… I guess you’d have to show that the real strings don’t sound or behave as shown in the video, however it was created.

In this case there's a difference between CGI and generative AI. However they came up with arrangement of pixels on the screen, the product is still portrayed accurately.

Now, unless the company in question got their new strings into Sona training data, I wager that the generated output has little casual connection with the product being advertised. If I found out IKEA's newest product looks nothing like on the commercial, because the ad was using generative AI and hallucinated something approximating the product, I'd be looking at it as fraudulent too.

IMO in D'addario's case, the analogy would be like using CGI and illustrations to illustrate a painting.

Also, I think when judged by the court of public opinion, the overwhelming answer was "yes, it's fraudulent", or at least "misleading and useless" as most people even complained that the song sounds like an overproduced mess where any string would sound the same.

Maybe they prompted "make it sound like the guitars have D'addario strings"