This bar only seems high because the bar in most companies is already unreasonably low. We had decades of research into functional programming, formal methods and specification languages. However, code monkey culture was cheaper and much more readily available. Enterprise software development has always been a race to the bottom, and the excitement for "vibe coding" is just the latest manifestation of its careless, thoughtless approach to programming.

But if push come to shove any other engineer can come in and debug your senior engineer code. That's why we insist on people creating easy to change code.

With auto generated code which almost no one will check or debug by hand, you want at least compiler level exactitude. Then changing "the code" is as easy as asking your code generator for new things. If people have to debug its output, then it does not help in making maintainable software unless it also generates "good" code.

There are limits how badly can such senior screw up, or more likely forget some corner case situation. And he/she is on top of their own code and whole codebase and getting better each time, changing only whats needed, reverting unnecessary changes, seeing bigger picture. That's (also) seniority.

Llm brings an illusion of that, a statistical model that may or may not hit what you need. Repeat the question twice and senior will be better at task the second time. LLM will produce simply different output, maybe.

Do you feel like you have a full control over whats happening here? Business has absolutely insatiable lust for control, and IT systems are an area of each business that C-suite always feel they have least control of.

Reproducibility and general trust is not something marginal but core of good deliveries. Just read this thread - llms have 0 of that.