could do a better job than him is laughable as ARod has probably forgotten more about football than 95% of CB will ever know.
However, recognizing that there's a problem and pointing out that the person responsible for fixing it isn't succeeding is a different matter. You don't need to be an expert to identify when something isn't working. For instance, you don't have to be a car mechanic to know when your car isn't running properly. You can recognize the issue without knowing how to fix it.
Similarly, if the current approach isn't solving the problem, it's reasonable to suggest bringing in someone with equal or greater expertise to try and fix it. The key difference is between acknowledging a problem and claiming you can solve it without the necessary expertise.