Everything's shitty in its own way. Modern (or even golden age era) movies, with top production values are equivalent of Egyptian wall paintings. They have specific style, specific way to show things. Over the years movie artists just figured out in what specific way the movies should be shitty and the audiences were taught that as a canon.

AI is shitty in its own new unique ways. And people don't like new. They want they old, polished shittiness they are used to.

While I agree that all art is kinda shitty in its own way (IMDB has sections dedicated to breaks in continuity and stuff like that), experienced filmmakers would be good at hiding the shittiness (maybe with a really clever action sequence or something).

It's only a matter of time before we get experienced AI filmmakers. I think we already have them, actually. It's clear that Coke does not employ them though.

It's an intentional new-media ad, so I think they're embracing the flaws rather than trying to hide them.

Also, since it's new media, nobody knows how to budget time or money to fix the flaws. It could be infinitely expensive.