@pjc
I bet there is some kind of "dunbar number" adjacent-equivalent thing going on with a ceiling on how many agents an engineer can run (as in how many parallel disciplined, human owned, responsible for the code in production, you can mentally manage) before which it all just gets away on you, and it moves into a new level of dangerous/lossy unexamined abstraction ("someone else's code, not understood, either architecture or syntax").