Eh, I feel the productivity argument kinda depends what sort of project you're using it for. If it's a local tool that only needs to solve a very specific problem you personally have, or you're treading well trodden ground represented in the data set (like WordPress plugin or React component development), you could probably just let an LLM handle almost everything and get a perfectly adequate solution in minutes.

And if you don't know anything about programming, or don't care that the solution it'll come up with is potentially flawed, then it's a lot quicker to vibe code up some sort of hack job answer than learn how to do everything manually. I'm pretty sure that my non-technical parents or grandparents could ask Claude or ChatGPT to build a simple website for their small business or charity, and have something workable within an hour or two.

For a software engineer, AI might not make them any more productive. For a non-engineer, it's basically magic.

The unsustainability thing is more of a concern though, and the external effects of AI are a huge problem. It's just that pure productivity wise, a lot of people will be significantly more productive with these systems than without them.