The value of work is related to all the costs and benefits of the work including the externalities. The usefulness of knowledge is based on its relationship with work. My economics knowledge has not been useful because I have never been in a position where my ignorance on the subject would be costly. My ability to obtain useful and valuable knowledge is dependent on my ability to recognize which kinds of knowledge are not useful to me at that point in time.
I care about being useful, valuable, pragmatic, efficient, and effective. I have imagined all kinds of explanations for all kinds of things. It is fun to imagine explanations and read science fiction. But I ultimately want explanations which are useful and valuable.
I am not a fan of particle accelerators because they have not proven to be useful nor valuable. Many people are doing work which has very little utility and value.
I like the idea that has been called skills stacking or resume building. Our work can be mostly useless in direct relation to creating a world without hunger and solving the human resource problem. But our work can be used to indirectly build prerequisite skills and relationships which are needed to solve these bigger problems. Ideally we are also building prerequisite technologies.
My explanation for why we don’t have a world without hunger is that people dont' really care enough to be critical of how they are using their time. I can’t find people who actually care about creating a world without hunger. A friend gave me links to websites where people allegedly care. But when I try to volunteer my skills and labor to them they don’t respond to me or they have no way for me to actually volunteer.
If you actually set your mind to volunteering your skills and labor with an organization that claims to have a noble mission you will often find that their claims are a lie. You can run this test. We can run this test together. We could build a database of organizations who claim to have missions which when tested are merely lies.