Bad code has real world consequences. Its not limited to having to rewrite it. The cost might also include sanctions, lost users, attrition, and other negative consequences you don’t just measure in dev hours
In theory experienced humans introduce less bugs. That sounds reasonable and believable, but anyone who's ever been paid to write software knows that finding reliable humans is not an easy task unless you're at a large established company.
Read the study to understand what it is measuring and how it was measured. As I understand parent's summary is fine, but you want to understand it first before repeating it to others.
In my experience, they are not even close.
I would frame it differently. There are developers successfully shipping product X. Those developer are, on average, as skilled as necessary to work on project X. else they would have moved on or the project would have failed.
Can LLMs produce the same level of quality as project X developers? The only projects I know of where this is true are toy and hobby projects.
Of course not, you have switched “quality” in this statement to modify the developer instead of their work. Regarding the work, each project, as you agree with me on from your reply, has an average quality for its code. Some developers bring that down on the whole, others bring it up. An LLM would have a place somewhere on that spectrum.
If you compare it to beautiful code written by true experts, then obviously not, but that kind of code isn't what makes the world go 'round.
The question is, what happens when you have a middling dev iterating with an LLM? And in that case, the drop in quality is probably non-linear---it can get pretty bad, pretty fast.