The worst that's happened, that I'm aware of, is I made a change with A.I. that I didn't realize broke something else (that I wasn't even aware our reports supported, it was new to me), and apparently QA didn't think to check for it either (although I did ask them specifically to verify everything in the report still worked), so it made it into Production, clients complained, and I was told about it and got it fixed over the next couple of days.
But that could have happened if I wasn't using A.I. also, because it wasn't something I was aware I had to check for and I could have also broken that same thing while doing the work manually.
We don't have AI agents do anything directly in Production, so I think this is about the worst that can happen with our setup right now.