That's always been my thought. There's so much internal monologue in Dune, how else are you going to represent it? The Scifi Channel and Villeneuve both seem to just kind of like, leave it out. Herbert's characters have rich internal lives, and arguably the most significant parts of Dune happen inside their heads.
The other adaptations maybe stayed closer to the source material for the details of the world in some aspects, but I think Lynch really nailed the feeling and some of the important ways of thinking that kind of get left out otherwise.
Thankfully, it seems like everybody's done a pretty good job with the source material so far. People grumble about the Scifi miniseries too, but it did a pretty great job conveying the first three books. I've been a life-long Dune fan and they all hit the mark for me. That's pretty rare in any adaptation, and I think it speaks to the strengths of the story itself and Herbert's fantastic world-building.
I can't even begin to try to like, rank my favorite Baron Harkonnen. They're all fantastic and take the character in pretty different directions.
Sure, but it's not really the same when it's stated out loud. It becomes less about characters plotting against one another and more about characters just like, talking really openly about their motivations.
It kind of suffers from that weirdness you see a lot in anime where a character who's completely alone will go into extreme detail about their plans or motivations. Basically an internal monologue, but delivered out loud into a space that's mid-way through the fourth wall.