Most people are employed in the course of something important and/or useful, even if it's tedious or boring.
There's a strong argument that some of the least skilled jobs provide some of our most critically important functions. Those positions are low paid because there are lot of people willing and able to do them, not because they aren't needed.
I think claiming "my work is meaningless" is just a broad expression of workplace dissatisfaction and not really specific enough to mean anything. The position itself likely has an important function or no one would be willing to pay for it.