I was completely gripped with the new Dune but God help her if she tries to watch Lawrence of Arabia, Tarkovsky (e.g. Stalker), or 2001. For me it works, I appreciate others might not like it but I thought the style was great.
I didn't expect to like it because I didn't really like the book. For me, this is one of the few times where I think the movie is better than the book.
I am glad that a film like that can even be made these days given that I think you're right about modern attention spans.
This is because directors usually don't have anything to do with the trailers (in fact, it's typically outsourced to companies who specialize in making them). Trailers tend to reflect what the studio execs want people to think the movie is about, which trends towards "what gets the most people to buy tickets?"
Sadly, I don't think this will ever change.
I did enjoy the movie, though. Villeneuve really did the book justice, and I cannot wait for part two.
It's also pretty horrible from past audiences' point of view given that they'd expect to see more than a prologue in a 155m film. Villenueve makes truly beautiful movies but it comes at a cost.
That dude had a certain style, cinematic intellectualism with beautiful cinematography. It's definitely not for everyone. Dune is that unique blend of world building, political intrigue, religious exploration, coming of age, and a tiny bit of action. Hard to get all of that in one movie, and the trailers made it seem more Star Wars than Blade Runner.
It's the sort of movie to watch when you're seeking quiet contemplation, not popcorn pulp...