Actually not even half as tacky as the other billboards in the area advertising weed.
This looks really AI-gen to me, particularly the game controller being held backwards and the blue background between parts of the hat, but I’m open to other perspectives if this seems human-made to you. As I mentioned before, it wouldn’t be unlike the local weed companies to make their ads as lazy, banal, facile, and meaningless as possible.
One hundred percent AI, also the issues you point (and the different number of fingers on each hand) can be easily corrected with basic basic basic Photoshop skills. Shouldn’t take you more than an hour as a complete beginner.
So yes they used ai and didn’t even bother polishing up.