The Auteur Theory is the theory he is describing. "The term “Auteur theory” is credited to the critics of the French film journal Cahiers du cinéma, many of which became the directors of the French New Wave.Aug 1, 2017"
Auteur's Theory (author, in French), emerged around 1954 and is primarily defended by François Truffaut. This method of film analysis was originally associated with Nouvelle Vague and critics writing in the magazine Cahiers du Cinéma. This assumption says that a single person owns a particular movie, that is, that movie is considered "yours," so many associate movies of particular directors with style films and own brands. “This is a Truffaut movie. From Tarantino. From Woody Allen. ” The director is considered the author of the entire movie, without worrying about the entire crew involved.
this is because the rhythm section is meant to support the ensemble. Yes the rhythm section does have solos however without the rhythm section the ensemble would sound dull and boring.