A new or rookie QB can be a leader during their first year. However, its' not going to happen if the HC or team sucks. Cause when that happens there's no stability. And when there's no stability from the head coach you have no leaders, cause you have to get it from the coach first.
If you have a good team or a coach that's in charge: The players that he really likes, automatically become designated leaders, if not adopted ones (by his teammates).
That's why great QB's are almost always associated with Great Coaches, or at the very least, very good or competent coaches. They go hand in hand.
I agree that a young QB can have leadership qualties, which I do believe Cam has naturally, but to actually take on the whole leadership role literally right off the bat, I doubt it.
Not all QBs are natural leaders either and some are quite happy leading their team without actually being the leaders of the team. That is where a good strong coach, who is a natural leader and good at his job, comes in. All you have to do is look no further than the Ravens team to see that Flacco maybe the leader because he's the QB but as far as who is the real leader of the team, it's not him. John Harbaugh is the leader and so is Ray Lewis.
As I stated before, the whole Cam is "immature" because those at NFLN follow him with a camera and spin his actions into something negative is silly. The way they go out of their way to paint Luck as such "the leader of men" is just as nauseating as them going out of their way to show that Cam isn't "mature enough to be a team leader." I'm sure both Cam and Luck will make great team leaders one day if left alone to grow and mature but it's somewhat naive to assume one is better than the other as leaders base on the manipulation by our media.
Also, let's be real, the whole media packaged Andrew Luck story is getting quite boring. He didn't "save the Colts" and brought them back from a brink of anything. The team has been in the play-offs every season except 2011 because Peyton went down and they wanted the number one pick when the chance came to get Luck. The team simply didn't waste their chance at getting Luck @ 1 by investing time and energy training their back-up QBs to win games. Plus, the media was squarely behind the Colts tanking their season to get Luck. It was their fairy-tale story also.