Extremely worthwhile question, long overdue. Productivity, especially in relevant areas like administration, stagnated despite computers hitting every desk. I read the Cowen book (Complacent Class) at the same time I was reader Graeber's "Bullshit Jobs." Heterodox writers from both sides of the spectrum. Same observation. On the face of it, it doesn't make sense. How could, for example, a local college's administrati…
I don't know if this has been quantified, but to some extent the extra capability is simply repurposed to more detailed administration. Things that were not possible become possible. Things that we did not have time for, we suddenly have time to do. Per Parkinson, "work expands so as to fill the time available for its completion".
An example would be logistics within the US -- at some point, probably after 9/11 or a similar event, it was decided that all packages flying in commercial airlines within the US needed to be vouched for by entities known to the US government, the individual packages tracked at a more detailed level, etc. This would not have been possible without automation throughout the industry, and definitely "soaked up" some of the productivity benefits of this automation.
I'm sure there are endless other examples.