@Ca_Gi @Antanicus @feonixrift What do you mean by "internal chat"?
#OSM uses many communication channels (IRC, mailing lists, slack, twitter, telegram, mastodon (ie here)), the OSM user diaries, OSM private messages. In theory you could try to "federate" them, but they are a tiny tiny tiny part of OSM, and nothing to do with edits, or the map data. So I'm not sure what benefit it would bring? And the main thing (the data) would still be centralized.