No one coming out of Idol would be where they are without idol. Not a single one.
Was Jennifer Hudson actively working on a singing career? Clay, Fantasia, Carrie, etc.?
A few Idols had been trying to make a go of things prior to the show, e.g. Kelly, Chris, Taylor, Diana, Katherine, and Bo who were making the rounds trying to get a musical career going. These folks MAY have made it without Idol only because they were at least tying, but odds are, they wouldn't have been successful without the show.
Sorry, but AI gave these people their breaks. Each and every one of them. And each and every one of them owes the show at least THAT.
On the flip side, success after the show has NOTHING to do with Idol - and EVERYTHING to do with management, career choices, and LUCK. Jennifer got lucky with Dream Girls. She would NEVER have been on the radar without Idol and she would never have known about the audition without idol. Still, she new to try out and work hard along the way. So, AI got her there, but she made it work after the fact.