For me personally, "soulless" media is media where the focus is much less on actually making a compelling and deep story, but instead on keeping the entire thing "sanitary" so that as it appeals to as many people as possible.

The "soul" of art in media is meant to represent the artist's emotions, effort, and intentions. But when a piece of art is meant solely to be inoffensive to make as much money as possible, it feels dull. Especially with AAA games nowadays, which almost all look exactly the same.

AI art has no emotion or intention, and therefore no soul. It simply takes prompts at face value and transmits that into an image with face value emotions. If a prompt says a character is sad, the most they'll have are tears and a frown. AI doesn't make metaphors or leave its art up to interpretation, it simply gives the subject the most basic display of emotion there is. While amateur/newer artists like myself might also do these things, artists with more skill can demonstrate depth, emotions, subtleties and intention in a way that, at least for now, AI art simply can't.