> Please share some examples.

Not the commenter you asked but the author of the original post here. I don't know about insufferable regulars but some channels like #emacs, #commonlisp, #esolang, etc. on irc.libera.chat do feel like social clubs but in a good sense. The same set of regulars can be seen everyday and people recognise each other by their nicknames. Further, I have found these channels to be very welcoming and kind to new members. Sorry I do not have examples of more "mainstream" channels that are also like social clubs and welcoming to new members. As an Emacser and Lisper myself, these are the channels I come across. But I am sure that "mainstream" channels which are social clubs and nice to new people do exist. Perhaps someone else can share some examples on this thread.

Now about regulars, many mainstream channels like #python, #rust, ##math, etc. have more or less the same set of regular and active members who answer on-topic/technical questions frequently. They don't exactly feel like "social clubs" to me. On the other hand they feel like small, tightly-knit, Q&A forums to me.