The most subtle thing to me is who has stake in the game. It is true that humans make mistakes too, but they would generally strive not to damage money-generating software/hardware infrastructure. If we remove all they people that actually understand how the system is working (up to a level of abstraction), how will the ambitious PO (or whoever is driving the AI) be safe from ruining the whole thing or simply landing in a deadlock situation where one agent wants to make the change (e.g. dev agent) and the other agent is refusing (QA agent)? I guess we are still trying to find the right level of abstraction and only evolution will show where it is.