Whilst the TV series was more faithful to the novel than Lynch's film, it lacked the epic scale required by the story. Just as Lawrence of Arabia shouldn't be a TV series, nor should Dune (or Lawrence of Arrakis, as I sometimes jokingly refer to it). I think Villenueve - a genuine cinematic visionary - did an extraordinary and satisfying job getting across the sheer scale of the thing.
Paul Atriedes is supposed to be fifteen in the novel, so I don't quite see what you're getting at with the physical poise thing. I thought Chalomet looked convincing (ie the right age) and handled himself convincingly in the fight scenes. We'll have to agree to disagree.
As for Call Me By Your Name, I brought it up purely as an example of Chalomet being a good actor. I'm not sure people would have been up in arms had he been a daughter though. There are loads of films of that kind that haven't resulted in uproar (An Education or Noce Blanche, for instance). :)