I'd actually argue that developers being actually sped up by LLMs (i.e. in terms of increasing their output of maintainable artifacts and not just lines of code

I'd actually argue that developers being actually sped up by LLMs (i.e. in terms of increasing their output of maintainable artifacts and not just lines of code) are those that have a good theory of the system they're working on. At least at this point, LLMs are great at the "how", but are often missing context for the "what" and "why" (whether that's because it's often not written down or not as prevalent in their training data).