There's some pretty good evidence that while a very small fraction of blue collar jobs are worthless, a much higher fraction of white collar jobs are in fact worthless.
https://tedbauer.medium.com/a-lot-of-knowledge-work-is-just-performative-nonsense-e71a154977d3
https://www.vox.com/money/23733244/bullshit-jobs-work-employment-lazy-jobless-employed-nothing-to-do