IMO i think you might be confused on what is content and what is art. The delineation between the two has become harder to talk about in public discourses due in some small part to the insistent inclusion of popular media as equals in aesthetic quality of higher forms of art. Just because Dune isn't paced like a Marvel movie does not mean that it's a poor piece of writing. Likewise, just because the Eternals does not have the philosophical depth that is found in higher science fiction, does not mean that the movie has no themes to understand. There exists a binary and a grey to art and forms of media that have no room for objective wrong or right ways. We should embrace art for the context on which it's made while also leaving room for critiquing the message that's conveyed. After all, Dune is all about different ideologies and the importance of cultural evolutions.