The language used suggests to me a possible cycle of ennui -> "a-ha" moments of emotional investment -> confusion as to why having rationalized a purpose doesn'

The language used suggests to me a possible cycle of ennui -> "a-ha" moments of emotional investment -> confusion as to why having rationalized a purpose doesn't lead to consistent gratification, or uncertainty over said purpose -> "what is my purpose?". Repeat. What you specified as something you love are abstractions, removed from the action/labor. There are many jobs that solve problems, there are many ways to innovate. You can try to convince yourself that x or y should feel meaningful because "it does something important", but that works both ways - you can just as easily think "none of this seems important at all". Ultimately, I don't think you can rationalize work as being meaningful - it just feels meaningful. Rationalizing it works temporarily (like in those "ah-ha" self-motivating moments), but not lastingly. If you were told that pressing a red button all day would save lives, would it feel meaningful? Next question: do you enjoy being at a desk writing code and shipping products? I think we need to look to our daily actions and behavior, get closer to the metal. What this reveals to me is that there is probably a broad range of labor I could find meaning in, and certain conditions really make or break enjoyment. Meaning is sensory to me, it's a question of achieving "flow" states. You could try to recalibrate things at your leisure too: get more social validation, get more exercise, work with your hands as a hobby, volunteer if you enjoy it - whatever is lacking.