Bullshit jobs exist because upper management can't know exactly what everybody in the company is doing, which leaves opportunities for middle management to advance their own interests at the expense of the company as a whole. Upper management might suspect jobs are bullshit, but it's risky for them to fire people because the job might actually be important.

But upper management can know exactly what LLMs are capable of, because they are products with fixed capabilities. ChatGPT is the same ChatGPT for everybody. This makes firing obsolete workers much safer.