My expectation is that there'll never be a single bust-up moment, no line-in-the-sand beyond which we'll be able to say "it doesn't work anymore."

Instead agent written code will get more and more complex, requiring more and more tokens (& NPU/GPU/RAM) to create/review/debug/modify, and will rapidly pass beyond any hope of a human understanding even for relatively simple projects (e.g. such as a banking app on your phone).

I wonder, however, whether the complexity will grow slower or faster than Moore's law and our collective ability to feed the AIs.

Maybe software systems will become more like biological organisms. Huge complexity with parts bordering on chaos, but still working reasonably well most of the time, until entropy takes its course.