"Productivity growth" just means same revenue for fewer employees. It would be ironic if that were the measure. (And no one argues that every business would benefit as expected when using the entire index as a signal.)

AI in medicine has become pervasive, resulting in less time spent fighting IT or staying up-to-date and more time with patients; no one need be fired because you can always do better work.

It's the opposite of enshittification: quality has gotten better without any visible economic difference.