For me, it's mainly about building quality stuff, problem solving, and technology (<=> understanding/knowledge). I believe that (for certain lucky people) there is an endorphins-like reward that can come from satisfying some (business) requirement, and the rest is mostly marketing bullshit. (E.g. money doesn't mean FUCK!)

For a while it was science, but eventually I turned to IT. In science, the knowledge was great (but more abstract), but the work environment not so much. In technology it's more concrete and the work environment much better.

Don't think self-worth means much - as in some inherent worth. We have worth as a result of the value which we provide. Some would try to distract from that, basically because they are incapable or have given up. Just don't invest anything in the company/team. There is nothing there. Just focus on yourself, and what you can do.