Hey there,
as many of you might know, there's an ongoing mass community effort to move away from the free wiki hoster Fandom (what used to be wikia or gamepedia) to self-hosted wikis. It's a similar campaign to the move to Lemmy, albeit much more successful.
Fandom is a predatory marketing and ad company that uses auto-play videos, has banners obscuring the content to a ridiculous degree, does not respect the work the editors put into their wikis, and after all makes their own sites super slow to use from all the ads, with ads loading in just as you want to click on a link, making the entire layout move to make you click on the ad after all. They're constantly trying to make the site into something of a "social media page" and are a prime example of so-called "enshittification".
Examples of these self-hosted anti-Fandom wiki efforts are the Baldur's Gate 3 wiki and the Elder Scrolls Pages. Even the Star Trek Online wiki has moved from Fandom to their own self-hosted variant, although their slow server choice leaves some things to be desired, and of course this very instance (startrek.website) also is a self-hosted indie initiative.
Memory Alpha and Memory Beta stand out in the world as excellent wikis that categorize most details about one of the most extensive franchises ever. They really deserve a clean, ad-free, self-controlled experience. I wanted to contribute to them forever (adding to Memory Beta as I read novels), but the idea of supporting Fandom with an active account makes me uncomfortable.
Does anyone know why they have not moved yet?
I don't see a reason why any self-respecting editor of an extensive wiki would like to stay on Fandom. It provides no benefits, and they have regularly sabotaged wiki projects.
I assume it's the standard inertia-type reasons: doing nothing is easier than changing a bunch of stuff, not changing involves fewer unknowns, and they probably have ad blockers and custom rules that mean they don't personally have to deal with the worst of it.