Honestly, Miraheze is interesting to me, as it's basically just fandom in a Wikipedia format. However, I have some questions about it:
I'm not going to start any articles about the platform, this is mostly just out of curiosity.
Check out their website directly and Discord channels. It has (too) little media coverage. It seems to be exponentially growing in volume, but maybe not as fast in quality of content and resources to support it. If you can help I think they would appreciate any help they can get. I also think Wikimedia should help and open up a more direct connection then just via individual Wikimedians and MediaWiki folx.
"as it's basically just fandom"
Well, that's part of what Miraheze does. They also host wikis that Fandom wouldn't touch, and host private wikis.
"What is the biggest "wiki" that the platform hosts?"
All The Tropes is at least an order of magnitude larger than any other wiki they host, and has been since Orain ceased operations.
(Fair disclosure; I'm a mod on All The Tropes.)
Done (Special:Diff/5697076)
The below edits are too manual, in some perspective.
If it is possible to store the data on wikidata:Q42671570 and load from it using Module:Wikibase, it would be nice I think.
I have no idea of whether it is appropriate to praise Miraheze or add more information (I am more of a Wikiversity/Wikipedia editor). But as far as I know, Miraheze permits private wikis that most closely resemble a MediaWiki project. I discovered Miraheze while contemplating a proposal requesting that Wikimedia make a private wiki for educational purposes. Students compete for grades, and the open structure of Wikiversity allows students undesirable access to each other's work in progress.
I have a "wikinode" at https://wright.miraheze.org/wiki/Main_Page that permits me to "peek" into the private work of 100 students, and Miraheze charged me '''nothing'''.
For more information about my participation in Miraheze, search for "Guy Vandegrift in https://meta.miraheze.org/wiki/Miraheze-2-year
For my effort to use wikipedia:OpenStax textbooks, see wikiversity:OpenStax College/Astronomy --~~~~
@Guy vandegrift nice that you took time to write this and contribute. This is indeed interesting case study. Got me thinking!