#2 Let Hangman Page develop a bit more
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On one hand, you have a guaranteed future WWE Hall of Famer and someone who will be remembered as one of the greatest Superstars in the history of pro-wrestling. Next, there's Hangman Page who is still a young gun at 28-years old and has a long way to go.
Giving the World Title to Jericho will help Page in the sense that he will be pushed to become a strong contender for Jericho's title. When he finally wins the title at some point, it will be a big moment that fans would go bananas over.
Defeating Jericho would immediately turn him into one of the biggest stars in the industry. All AEW needs to do is build him up a bit more, before handing him the top prize.
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#1 Incredible star power
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It's clear as day: Chris Jericho comes with a lot of star power and he isn't wrong when he continuously talks about being responsible for AEW's popularity. The company consists of a large crop of talented athletes, but none is as popular as Jericho.
He has over two decades of rich history behind his Hall of Fame career, and that's the biggest reason why AEW should make him its first-ever World Champion.
Jericho winning the title is bound to be a way bigger deal than Page's win ever would. It would also give rise to a string of matchups against the top faces of the company and a heel Jericho.