David Graeber’s exceptionally perceptive essay has since been expanded to book form by its author: https://strikemag.org/bullshit-jobs/
An interesting question raised by your analysis, pgp, is whether corporate executive suites understand which employees actually generate wealth, and which are simply holding the positions described in the essay. I think it’s entirely possible that our existing top managers will discard the muscle and tendon and keep the pretty hair. Of course, it’s also possible that all the folks with degrees in management and grant-processing will get laid off while the factory workers stay employed. Either way, one class of people is going to be extremely unhappy.
Interesting times.