It "obviously" does based on what, exactly? For most devs (and it appears you, based on your comments) the answer is "their own subjective impressions", but that METR study (https://arxiv.org/pdf/2507.09089) should have completely killed any illusions that that is a reliable metric (note: this argument works regardless of how much LLMs have improved since the study period, because it's about how accurate dev's impressions are, not how good the LLMs actually were).
It's a good study. I also believe it is not an easy skill to learn. I would not say I have 10x output but easily 20%
When I was early in use of it I would say I sped up 4x but now after using it heavily for a long time some days it's 20% other days -20%
It's a very difficuly technology to know when you're one or the other.
The real thing to note is when you "feel" lazy and using AI you are almost certainly in the -20% category. I've had days of not thinking and I have to revert all the code from that day because AI jacked it up so much.
To get that speed up you need to be truly focused 100% or risk death by a thousand cuts.
not OP but I have a hard metric for you.
AI multiplied the amount of code I committed last month by 5x and it's exactly the code I would have written manually. Because I review every line.
model: Claude Sonnet 3.5/4.5 in VSCode GitHub Copilot. (GPT Codex and Gemini are good too)
Yes, self-reported productivity is unreliable, but there have been other, larger, more rigorous, empirical studies on real-world tasks which we should be talking about instead. The majority of them consistently show a productivity boost. A thread that mentions and briefly discusses some of those:
https://news.ycombinator.com/item?id=45379452