Earlier quoted context omitted.
Perhaps obviously, when your interpretation makes the article not make sense, it's useful to try interpretations that work. I guess another way to put it is that a very human mistake to make is to infer something and assume it was implied, then use that assumption to form a dismissal. I get that your particular interpretation is likely meant as some subtle manner of dismissal of the Koch brothers (something along the…
This is a spreadsheet, not an article, so I'm confused about your first point. When looking at a list of billionaires, it's natural to wonder "where did this fortune come from?", and in the case of the Koch brothers, the answer is "oil". I don't think it requires a deep dive into my psyche to defend this interpretation of the "source" field, though I'm always happy to swim around down there.
What's the source of my wealth in this case?
(this seems to be a clarifying exaggeration of what is being asked here)