I think a better framework to think about this is 'Bullshit Businesses', not bullshit jobs. A lot of companies only exist to make the owners/investors rich, provide little to no value to the world, and/or rely on dirt cheap labor for the economics to work. Think spammy call centers, Walmart, amazon warehouses, etc...

If people were not in desperate need of a paycheck and were able to negotiate/hold out for better jobs, or spend more time on career training, then a lot of the business would not exist, or would be forced to treat their employees better.