The director needn't be any more of an authority than anyone else working on a film.
Ideally it would be an equal collaboration between various artists and technicians.
The idea of a director enforcing their 'vision' on everyone else involved in the production doesn't need to be taken for granted.
The others should have a voice regarding their part in the process and anyone that refuses them that voice is an authoritarian.
Directing a scene is one task among many. A director has a role to play. How the role is played isn't written in stone.
Who says there even needs to be one director? Some directors are great at giving direction to actors while others are better with the technical or visual aspects.
Why not 3 directors? 6 directors? Maybe even abandon the 'director' role altogether and try to replace it with something more equitable and collaborative.
There's no reason a film can't be created with a horizontal process.
But film is already a big collaboration between hundreds of people. If someone really wanted their singular vision to be the only thing that ended up on the screen, they'd have to be the only person involved in the production. Write it, shoot it, score it, edit it themselves and act out all the parts.