That would be a horrible idea. Having two of the biggest stars in wrestling, fight the month before a WrestleMania? That's heat suicide. AJ Styles needs to start off small, and build up. Going after the biggest fish never works. He needs to be proven to the casual wrestling fan before making his way to feuding with Triple H, at a C PPV.
I don't know in what way you think that would of been "perfect." I can only assume you figured Sting vs. Triple H at TLC 2014, was also a good idea.
AJ styles vs HHH would of been more entertaining than this lukewarm feud he is having with Jericho. At least AJ's first defeat could of been against HHH for the title on a PPV instead of Y2J on a episode of Smackdown. And I don't get why this would HAVE to be a Wrestlemania matcg either. They already have a bigger main event for Fastlane then they are planning for Mania (HHH vs Reigns). Plus I definitely think it's dumb to have Triple H win the title, not compete in 1 big match where he goes over, and then just drop the belt at Mania. It looks so weak. And actually yeah Sting vs HHH probably should of happened at TLC because their match was fuckin shitty anyways, Taker vs Sting would of been better.