I think the word asset is being used in a particular sense here. Page views are not liquid or transferable.
The WMF is mission-driven. A large swath of their funds are spent as grants to other organisations, and they could par that back without affecting their ability to operate.
[disc: Wikipedian since 2004, many friends who are WMF employees]
Sure, but can they? Seems like an ever expanding cash sink, according to those financials...
I guess more concretely, the wikipedia.org domain is a very valuable asset.