WHO wasn't supposed to be a tool of soft power, and the fact it turned to one makes the decision to leave it all more valid. What soft power does a healthcare organisation provide, that couldnt be better served by your own means?

How do you feel about something like the International Atomic Energy Agency?

I think you're confusing soft power with hard power.

Showing up to do work is how you wield soft power nonetheless, even if it's a side effect.