I see where you're coming from. I remember there being another thread where if you had to have a new "expansion draft" with current players and your team had the top pick, you would take Luck because he's got a better future ahead of him because of his youth.
It's not even so much "his potential for the future" as it is the "right now, 1 game, do I think he has elite talent and capabilities." The only way I could leave him off any listing of elite QBs is if elite is directly tied to total body of work in the past, and even then, only because he hasn't been around as long.
Still, if I am playing a game tomorrow, and I can have any QB in the NFL for that game, Luck doesn't slip outside my top-5, which I feel makes him an elite QB.