No, one thing that would happen is that many projects would never be undertaken - basically, there's latent demand for software that would simply go unmet, because of resource constraints.

I was recently involved in a case like this - we had a critical part of our system based on a dependency that's no longer maintained. Previously, we would have just carried on for a year or more, living with the limitations until it was much closer to being entirely untenable, because rewriting the code in question would have been a multi-month project involving multiple developers, QA, and management time. But now, the code in question was migrated in a few days using AI, along with a suite of new tests in addition to our existing ones, that gave us a lot of confidence in the results. The productivity improvement here is at least on the order of 25x, possibly higher.

But most developers aren't sitting at their desks operating at a 25x pace all day, every day, so average productivity improvement is going to be lower. And of course, some use of AI will be suboptimal or problematic: waste due to e.g. duplicate development which happens when development is so easy, or costs for cleanup of mistakes.

We also now have a slew of AI-generated internal tools, most of which would never have been developed before. Many of them are very useful, the kind of thing that's on your eternal wishlist but never gets done. Some are kinda useless, so represent wasted resources. It's difficult to measure the productivity benefit of all this, because you'd have to compare it to the non-existent company without those tools.

Ultimately, measuring all this meaningfully is not really that feasible, except perhaps over the long term. Managers operate on vibes with this kind of thing because in many cases, that's all you can really do.