Maybe we are interpreting the GP differently. In this scenario, the phone tree is doing the same questions that the human agent is going to do but does it immediately when I call rather than "waiting for an operator" to ask me those questions. And as long as I can "press 0 to eject" (just like I can in the accounting scenario, then its completely kosher to me.

No, we end up with crappy systems because people are optimizing to save money over providing a good service. OP has simply replaced the traditional room full of clerks applying policy rigorously with a baysian algorithm and now AI. The management and oversight is still in place, and that is what makes a system that doesn't suck. To make it suck and save money, you remove access to that oversight or just remove it all together. And falling down that slippery slope is not inevitable, even if it sometimes seems like it is.

Regarding customer support on phone: I usually have lock with just waiting and not responding to the tel bot, very often you are routed to a human at the end :-D