did you mean to reply to my comment? if yes, can I ask you to explain what do you mean by assumption? where is that coming from?
regarding WMF (and other non-profits, like Mozilla), this is a well-known phenomenon - regarding C-suite compensation (it's usually about risk aversion, and that the board or whatever foundations have, is also usually sitting on other non-profits, and rarely they optimize by moving to the cheapest place and hiring folks for much cheaper, etc)
https://www.charitynavigator.org/discover-charities/best-cha...
but see also
https://www.givingwhatwecan.org/blog/arent-the-best-charitie...
and
https://www.givewell.org/