If Ziggler is leading and if he's been genuinely frustrated, it's kinda hard for me to see why. He's obviously made a lot of money in WWE or I just don't think he'd have stuck around signing new deals with the company all this time, so leaving due to money doesn't really hold a lot of water. The only thing that I can really think of is that Ziggler is someone who's wanted to be a consistent main event level guy, whereby he'd probably wind up making even more money, and he's not been at that level. Generally speaking, Ziggler has never really been above the upper mid-card level, even as World Heavyweight Champion due to the fact that the WHC essentially occupied the Intercontinental Championship's spot on the title tier when you get right down to it as the WHC hadn't been booked to be on the same level as the WWE Championship probably the Undertaker's last run with the title ended. Ziggler has to have known for a good many years now that he wasn't going to be a main eventer in WWE.

If he's leaving and plans to try his luck in AEW, he's not going to be the main event guy there either if that's what he's hoping. He's 38.5 years old and even though he's a good decade younger than Chris Jericho, he's not Chris Jericho in that he doesn't have Jericho's charisma nor has he had nearly as high profile of a career, which were major factors why New Japan was interested in working with him and why AEW wanted him.