It seems that most mailing lists occasionally have meta-discussions about what is on-topic, the few that don’t are the ones that have very strong moderation – authoritarian moderators who jump on the first infraction and clearly specify the rules.
I don’t recall the list of acceptable topics for any mailing list including “also discussions about what is on-topic“. As this is the Internet I’m sure that someone will immediately point out an example of such a list, but apart from the counter-example that someone will provide it seems obvious that for the majority of mailing lists a meta-discussion is not strictly on topic.
Regardless of a meta-discussion not being on-topic I don’t think there’s anything wrong with such a discussion on occasion. But if a meta-discussion is to be based on the volume of off-topic messages it would be nice if the people who advocate such a position could try and encourage the discussion in a way that reduced the number of messages. Replying to lots of messages is not a good strategy if your position is that there are too many messages.
If a meta-discussion is going to be about moving off-topic discussions to other forums that are more appropriate then it would be nice to have the meta-discussion move to another forum if possible. My previous post which advocates creating a separate mailing list for chatty messages was an attempt to move a discussion to a different forum . Anyone who believes that such discussions don’t belong on a list such as debian-private is free to commit their thoughts to some place that they consider more appropriate and provide the URL to any interested parties. I think that it’s worth noting that the only comment on my previous post is one that describes how to filter mail to split the traffic from the debian-private list into different mailboxes. I had hoped that other people would write blog posts advocating their positions which would allow us to consider the merits of various ideas without the he-said-she-said element of mailing list discussions.
Most mailing lists have a policy against profanity and some go further and ban personal abuse. Therefore it seems hypocritical to advocate a strict interpretation of the rules in regard to what is on-topic while also breaking the rules regarding profanity or personal abuse. I don’t think it’s asking a lot to suggest that the small minority of messages that someone writes on the topic of a list meta-discussion should obey the set of rules that they advocate – I’m not suggesting that someone should obey all the rules all the time, just when they are trying to enforce them. Also you can argue that a list policy against profanity doesn’t preclude sending profane messages off-list, but if the off-list messages are for the purpose of promoting the list rules it still seems hypocritical to use profanity.
It is a fair point that off-topic discussions and jokes can distract people from important issues and derail important discussions. It would be good if people who take such positions would implement them in terms of meta-discussions. If the purpose of a meta-discussion is to avoid distraction from important issues then it seems like a really good idea to try and avoid distraction in the meta-discussion thread.
I wonder whether a meta-discussion can provide anything other than a source of lulz for all the people who don’t care about the issue in question. The meta-discussions in the Debian project seem to always result in nothing changing, not even when the majority of people who comment agree that the current situation is not ideal. When an almost identical meta-discussion happens regularly it seems particularly pointless to start such a discussion for the purpose of reducing off-topic content. Revisiting an old discussion can do some good when circumstances change or when someone has some new insight. I know that it’s difficult to avoid being sucked into such discussions, when I was diagnosed with AS  I decided to try and minimise my involvement in such discussions – but I haven’t been as successful at doing so as I had hoped.