I have my issues with Iger, a lot of them actually, but NO ONE is walking into a position like that and turning everything around in two years. The extension makes sense. Disney was floundering under Chapek and no, I don't believe for a second Chapek didn't have enough power to do damage. Ripping something down is SO much easier than building it up and Chapek did a great job of that.
I could walk into my business tomorrow, p-off everyone to the point they leave and then need to spend the next five years building it back up to where it was. One day to undo years of work.
Take Imagineering for example, they may not have been Iger's biggest fan but they could work with him. In less than a year under Chapek we saw retirements, petitions for him to be fired, layoffs and the top guys leaving saying "F-it, I'd rather work on airport lounges". Meanwhile, Chapek isn't bothering to replace most of them and when he does it is with people specializing in interior hospital design or whatever it was.
Two years is not long enough to implement changes at a company of this size and see any obvious results. On the studio side, you can barely release a movie in two years in normal times and there is no chance of that with massive strikes. While at the parks, it likely takes longer than two years to even properly plan a new ride/expansion let alone having to staff back up to even start the process.
Bottom line, if he gets another extension and things aren't going much better, I'll help you pack his bags and buy you a beer after.