I am also confused how this project improves upon Wikipedia's moderation issues. Especially calling Ibis "federated", is it more "federated" than Wikipedia is?

It's also not like Wikipedia is unusable because of these issues. As with any source of information it is necessary to be skeptical with wikipedia articles. Wikipedia has the major advantage over any other source that the edit history is public.

And even though there are many incidents with Wikipedia's moderation, the website has also existed for a long time now and contains millions of articles. With the scope and size of Wikipedia some incidents are expected.

Wikipedia also compiles their own backup collections.[1] If at any point Wikipedia becomes actually unusable anyone could use the existing article to produce a new alternative database.

[1]: https://en.wikipedia.org/wiki/Wikipedia:Database_download