Really interesting piece.
I don’t think they can be compared outside of the world-building sense and both do a masterful job at that. Both series are considered cult classics, of course, but Tolkien made it into the mainstream. Not quite sure why, perhaps because he hooked young readers with The Hobbit and they grew into adults who wanted to follow the story? That’s probably too simple though.
My fav? Dune. No hesitation. I read it young and was hooked although some of the later books and the Lynch movie disappointed me.
I read The Hobbit in school and enjoyed it but somehow avoided the LotR books until after Jackson did his stuff. Unusually for me, I prefer the LotR movies to the books whereas the screen adaptations of Dune were, for me, underwhelming.