Whilst I agree with you, the Director's job is not to record sound, edit the picture or mix the ADR.
The Director's job is the actors. A Director is primarily focussed on the actors and then discussing with the DP about the shots.
As I've mentioned previously, it can depend on the film as to how much responsibility the Director has over the other aspects, most Director's must 'okay' everything before it gets on screen (ie costuem decisions, prop decisions etc.) but their main focus is the actor and the actor's performance. At the end of the day, the film is the Producer's even if the Director will cop the flak for a bad film.
I have absolutely no idea where you've got this idea from. I've worked with dozens of directors in my 20 years as a professional, I've met and discussed film with hundreds more and I've exchanged experiences with hundreds of my professional peers. Not a single one of them would share your view on the role of the film director. Of course the Director's role is not to record the sound, edit the picture or mix the ADR, any more than it's the Director's role to act in the film. The Director's role is to direct the film, all of it, not just the actors, maybe you're getting confused with the role of Acting Coach? I've never known a director not to spend every single minute of the picture editing not sat next to the editor. A director not to direct all the ADR sessions or not to be directing the final mix is unthinkable! I've never even heard of such a thing, let alone experienced it. Producers maybe very pro-active or you may rarely see them but whatever the level of direct involvement of the producer, the director is always present, directing.
While not using any live actors, I'm sure Pixar will be delighted to learn they no longer need to employ a director, they can leave it all to the Producer, CGI Supervisor, Supervising Sound Editor and other department heads. Your assertion of the director's role or main role is quite frankly ridiculous!
My point was - every other department has a specialist in charge of it.... A Director hires experts in other fields so that they can focus on acting.
Not only is your information incorrect but your argument makes no logical sense. First of all, contrary to your statement above, not one of the creative departments have a specialist in charge of them. Take for example sound, the Supervising Sound Editor is, as the title suggests, a supervisor, the head of the sound department, but the supervising sound editor is not in charge of the sound, the Director is! Logically, your argument only makes sense if the director does all the acting themselves but of course they don't, they hire acting specialists (actors) to do the acting, the same as they hire a specialist editor, DOP, composer or supervising sound editor and all of them require an equal amount of focus and directing.
The directors job is pretty much identical to the orchestra conductor's job. The orchestral musician's job is to creatively interpret their part of the score, the conductor's job is to provide an overall vision of the whole score and to accomplish this the conductor must direct the musicians' interpretations. Without a conductor, the performance would be a chaos of different musicians' interpretations. So it is with the director and the making of a film.
The equivalent of what you're suggesting would be a conductor whose primary focus is the 1st Violins and who lets the principle horn, principle cello and all the other section principles get on with it themselves (because they are in charge of their department) and your argument for this would be, they are the specialists and what's the point of having section principles if it's not to allow the conductor to focus on the 1st Violins?!
G