I’m not sure why Beehaw is coming up specifically in recent day (did something happen that I missed? E: Yes, a new write up from the Beehaw team, see Blaze’s reply), but their moderation issues and needs came up as early as June and July of last year, but was definitely being talked about by September between Beehaw admins and users. Here’s the thread I remember on it.
Another thread on one of the major CSAM content attack events against Lemmy (the one that took out vlemmy.net as you probably will recall) highlighted their desire for a better platform.
I’m OOTL if anything specific happened between the Lemmy devs and Beehaw admins this week that caused more beef, but the mindset that the development of much needed moderation features was progressing too slowly was with the Beehaw admins for many months now.