These are good points. I’ll lead with the fact Arrival was my favorite film of 2016 and I loved Blade Runner 2049. Slow isn’t generally an issue for me…
…if it’s engaging, and that was my problem with Dune. I never cared. Villains wander in for a scene or two, seemingly to set up another movie. Paul is an unengaging cypher. Major characters just vanish. @Amorphous and I spent time after the screening puzzling out whether one of the stars died or just disappeared to pop back up in the sequel.
It’s all world-building with very little in the way of character.
For me, at least!