I had a very different interpretation of the monologing in the first book. Some time has passed since my last read but I distinctly remember at least Baron Hark

I had a very different interpretation of the monologing in the first book. Some time has passed since my last read but I distinctly remember at least Baron Harkonnen having a self important but buffoonish inner monologe and at least one instance of a pov jump to another character who is thinking (paraphrasing) "this guy is a decadent buffon". I think the other characters also have melodramatic and self centered inner thought lives but I thought it implicit that their thought lives are limited and narrow generally, they often don't really represent to the truth of things and it's clear they are often overthinking things instead of communicating clearly and truthfully (like the Thufir's inner thought life is super far off base and he's supposed to be a near super intelligence.) Paul particularly seemed like, all things being equal, a self absorbed teenager. That was just my take though.