10,000 line workers can easily be replaced by another 10,000 people with (likely) little to no education, credentials, etc... CEO on the other hand? Doubt it.
Contribution as a term here is fluffy. I know what you are getting at but it makes no sense using it for some sort of comparison.
What you need to look at is impact of decisions. If the CEO makes a wrong decision the entire company can go down. If a worker makes a wrong decision it's much less of an issue.
Contribution is a term that can be pinned down (I suggested using a sensitivity analysis above).
I don't see any particular justification for "What you need to look at is impact of decisions." Why is "impact of decisions" a more important criterion than "who does the work."
