In addition to being a fun Turn of phrase, this is the question of whether someone else could do the job you do at least as well as you do it for the same compensation.
In other words, if you are in a specialized role that you are highly qualified and competent at performing, the opportunity cost of you leaving your job is high since it will be hard to replace you.
Many (currently, most) will not have the opportunity or good fortune to worry about this higher order problem, as they will be happy to be satisfy their basic needs first. In that way, this presupposes Full security of human rights.
So this is pretty much the idea of Replaceability that is discussed in the Effective Altruism community, though I am thinking of the idea in a more generalized way (how your work impacts everything, not just morally good outcomes). Here is some more reading on the idea: