Remember when computers and automation promosed to give us all this free time? Turns out it just meant companies could pay one person to do the job of four.
I say this while sipping my morning coffee, browsing HN and waiting for an amount of computation to finish on a single machine that required either a supercomputer or multi-million dollar cluster 20 years ago.
Which is an insane amount of time and probably does not actually increase productivity. The math does not check out as you claimed though.