Earlier quoted context omitted.
With most OSS projects nowadays I don't think you have to use a mailing list or anything that would have an MOTD in order to contribute. Contributions nowadays are often done entirely through the repository, so it makes sense to put in them the things that people contemplating contribution should be cognizant of. Repositories for most projects are more project repositories than mere code repositories.
> Repositories for most projects are more project repositories than mere code repositories. Indeed, but for some reason it still feels odd. I've acknowledged I'm getting old, right? ;-) Also, there is some rational justification to my feeling. It used to be that you might kick-ban someone from a channel or /dev/null their mailing list contributions. But if they made a technically meritorious merge request via SCM the…
But there are other ways to deal with actions that go against a code of conduct, to de-escalate situations and encourage rehabilitation within the project - just like what a healthy project would do without an explicit code of conduct.
Because let's be honest - those hobby groups you're talking about almost certainly did have a code of conduct, but it was probably implicit and uncodified.