Are you measuring the right metric?
This feels like an on going lack-of-understanding in the industry.
In manufacturing, economies of scale and automation work because you're physically making more objects and objects inherently have value.
For software, making more software doesn't mean you can sell more units of software. The unit price of selling existing software is already 0. Economies of scale do not exist.
The OP says: net business output is not up as a result of AI.
So:
…if your team is doing more work and being more productive…
That just means the productivity of your team (or software teams in general) maybe doesn't have a meaningful business impact.
You should be worried if so. That means productivity = work force reduction (reduce fixed costs for the business).