The parent commenter's experience pretty much sums up my experience with every IVR system, AI or not. The IVR cannot do anything I can't do on the website or the app. I wouldn't be calling if I could get the job done without calling them, so my experience is simply that the IVR is simply an obstacle to talking to a human. Very often the first human I talk to is simply an obstacle to talking to the second human, because the first human is so limited in their knowledge and authority that they can't do anything I can't do with the website or app either.

I don't really think this is an implementation problem or incompetence. AI is just not reliable enough yet to deal with long tail situations, especially in cases where the most common procedures don't apply. You can't give it the authority to override common-case business rules or make financially consequential decisions, because it will be manipulated/prompt injected by fraudsters.