I watched the new movie, got into sci-fi books a little later and read the entire Dune series (rewatched the movie after the first book for fresh comparison). There was a lot the was kinda glossed over, but the main theme of fremen and why the water was kinda devoid.
Thats not ringing any bells so I googled it, seems to be a movie replacement for the prana-bindu wierding, so makes sense for it to seem odd. I’ve never watched it, before my time… haha I’ve been meaning to though.