There’s plenty of potential leaders on a team, but there’s one guy paid to complete passes, Tebow had that job title but did not perform the job thus he is gone. And he didn’t have excellent ball control, his throw land in random place on the field, and “scoring efficiency” is a euphemism for “didn’t throw the ball much”. One of my favorite Maddenisms revolves around guys that get a lot of 4th quarter comebacks “the first part of a 4th quarter comeback is being behind after 3”, most coaches would rather have a QB that completes passes in ALL quarters so he doesn’t have to pull miracle comes from behind all the time.
Ball control means no turnovers and he did that well in the games he won, which was the majority. The leader of the team on the field is always considered to be the QB, especially when that QB is Tim Tebow.