Ferrari has released an interview in which they state that:
Next year they will not have a first and a second driver, and LeClerc and Sainz will start on equal terms and it will be the track that will decide who will be the captain of the team.
(which is however different in Redbull and Mercedes where they clearly have the two fixed captains)
I think if your team is in a contest with another team for the championship, as it was with Red Bull and Mercedes this year, then you have to favour whichever of your drivers has the most points. It's only logical. And this is what Ferrari are saying, if LeClerc is fighting for the title, Sainz becomes #2, and the same the other way around. This is exactly how it should be for all teams. It might be difficult to imagine at Red Bull, Perez fighting for the title and Verstappen with lower points (and the same with Russell and Hamilton at Mercedes)... but in this circumstance the team would surely order Verstappen (or Hamilton) to let Perez (or Russell) through.