[sbuttgereit]

This one is probably worth adding to your list:

https://erlangforums.com/

It may not have been a thing back in 2012. To be fair, I'm not sure how the forums and the mailing list compare/contrast in terms of what you can get/what's more popular/etc.

[macintux]

I haven’t updated this in a while, so it too probably has broken links.

https://gist.github.com/macintux/6349828