> “why engineer something fundamentally well at the start if there it is zero cost to fix it later when problems actually show up?”
Because this is a myth. it is not true that there is zero cost to fix it. LLMs become less effective the more convoluted codebases become just like humans, if only at a different rate.
Is there something about an LLM that makes it incapable of simplifying a codebase? I have only seen that the slop jockeys who wield LLMs most ardently don't seem to care about that, and that older models were worse at everything, including that.