Many of the chapters are still in "startup mode" - a challenge that the WMF should avoid when targeting organizations for sponsorship or donation. Perhaps more saliently, OSM, MariaDB, Internet Archive etc. are not representing the Wikimedia movement, aren't using Wikimedia trademarks, and presumably would receive a much, much smaller portion of their total operating revenue from the WMF than chapters typically expect. All good reasons why the WMF should not treat them in the same manner as Wikimedia chapters, user groups or thematic orgs.