The million dollar (perhaps literally) question is – could @kentonv have written this library quicker by himself without any AI help?
But what if you only need 2 kentonv's instead of 20 at the end? Do you assume we'll find enough new tasks that will occupy the other 18? I think that's the question.
And the author is implementing a fairly technical project in this case. How about routine LoB app development?
This is likely where all this will end up. I have doubts that AI will replace all engineers, but I have no doubt in my mind that we'll certainly need a lot less engineers.
A not so dissimilar thing happened in the sysadmin world (my career) when everything transitioned from ClickOps to the cloud & Infrastructure as Code. Infrastructure that needed 10 sysadmins to manage now only needed 1 or 2 infrastructure folks.
The role still exists, but the quantity needed is drastically reduced. The work that I do now by myself would have needed an entire team before AWS/Ansible/Terraform, etc.
But if the time it takes an engineer to build any one thing goes down, now there are a lot more things that are cost effective.
Consider niche use cases. Every company tends to have custom processes and workflows. Think about being an accountant at one company vs. another -- while a lot of the job is the same, there will always be parts that are significantly different. Those bespoke processes often involve manual labor because off-the-shelf accounting software cannot add custom features for every company.
But what if it could? What if an engineer working with AI could knock out customer-specific features 10x as fast as they could in the past. Now it actually makes sense to build those features, to improve the productivity of each company's accounting department.
It's hard to say if demand for engineers will go down or up. I'm not pretending to know for sure. But I can see a possibility that we actually have way more developers in coming years!
LLMs don't change that. If a business does not have the budget for a software engineer, LLMs won't make up budget headroom for it either. What LLMs do is allow engineers to iterate faster, and work on more tasks. This means less jobs.
But what has happened instead is that we are now building much more buildings and much more complex ones than we ever would have even conceived of back then. The Three Gorges dam required the work of thousands or even tens of thousands of people when it was built, and it would have required the work of millions in the year 1000. But it didn't actually generate millions of jobs in the year 1000: it was in fact never even conceived of as a possibility, much less attempted.
Of course, the opposite can also happen. The number of carpenters has reduced to almost nothing, when it used to be a major profession, and there are many other professions that have entirely disappeared.