Without wanting to get into spicy flame-war territory ... having a successful casual chat community sounds like the sort of thing beehaw would do better at than the rest of lemmy, in part, because community creation is closed, so arbitrary content naturally goes into the chat/lounge community, rather than into the very specific niche community it's most aligned with despite no one being in there and no one ever seeing the post (exaggerated but you get my point).
As I remember, casual conversation on reddit was also a bit low on traffic compared to other communities. Maybe we need to be more proactive by plugging relative communities in other threads.
It's just a numbers thing. The subreddit was fairly low comment, compared to subscribers. It succeeded very well at being casual. This C/ is doing fine compared to most of the niche communities overall, imo.