The might be leaving to other newer alternatives like blockchain-based Everipedia.org or Golden.com (which recently raised from a16z).
EDIT: Looking at both websites, neither of them seem remotely in the same market as Wikipedia.
How are the two sites not remotely in the same market? They are literally knowledge bases. Albeit, Golden is focusing more on structured data similar to Wikidata.org and Everipedia.org is focusing more on blockchain related content first with the backend using smart contracts/token incentivization.