Iger left so he could collect his stock while it was high and before it crashed. But there's little in my mind to suggest that things would've been this bad had Iger stayed on board. Iger just didn't want to deal with COVID so Chapek got lucky and was named CEO.
I urge you guys to read the article I linked. Iger is reportedly not happy with Chapek's direction. No one is. People at Disney actually liked Iger, in part because he came from Entertainment, where Chapek is strictly a business guy. And he's not that good at it tbh. He has torn down the culture of Iger's Disney, where creatives were allowed to do their thing as long as they continued to churn out a solid project. Under Chapek, the creatives do their thing and then now have absolutely no say in how or where it is released, which is pissing everyone off.
He has also put in place, as the head of Disney Digital Media Distribution one of his buddies from Consumer Products. That's right, a paper pusher is the overlord of every single creative at Disney. He's there ahead of the bosses of Pixar/WDAS, Kathleen Kennedy, Kevin Feige, Alan Horn, everyone on the Fox side, etc. Again, this guy is not qualified to fill this position in any way, he only has the job because he's buddies with new Bob. And everyone hates him for it. Again, say what you will about Iger, but he always put people actually in the entertainment industry in the leadership positions.
And mind you, this guys position is just a new, Chapek created middle-man position that gets to decide if a Pixar film, a film that was worked on for at minimum 3 years, goes to theaters or just goes to Disney+ at no extra charge.