People on call will use AI as well. As long as the first AI left enough documentation and implemented traceability, the diagnosing AI should have an easier time proposing a fix. Ideally, AI would prepare the PR or rollback plan. In a utopia, AI would execute it and recover the system until a human wakes up.

Or at least there is something to chat with about the issue at 3am.

This. I've been a sysadmin for a quarter of a century and have professionally written next to no software. I've debugged every system I've had to support at some point though. It's a very different skill set.

True, but I think the implication (as I read it) is that AI may be providing more complex solutions than were needed for the problem and perhaps more complex than a human engineer would have provided.

it's MUCH worse now, not just because of the massive amount of code generated with zero supervision or very little supervision, but also because of the speed at which the systems grow in function