I think in this case the product is the scene and not the picture though. If one could copyright the result of a prompt then I assume no one else could use the same (or very similar) prompt for profit as it is likely to produce similar code whereas a scene can be photographed for profit by anyone regardless if a similar picture has already been taken, or so I assume. If Andy Warhol just photographed Prince in a same/similar pose and clothes would there be the lawsuit case ? I don't think so.
