I just noticed that the link to the forums ("NeXT Community") in the sidebar of http://index.nextcommunity.net doesn't work, it points to https://www.nextcommunity.net/forums/ which gives a 404.
Simply using https://nextcommunity.net/forums/ works, this looks like a DNS config error?
Corrected! Thanks for the note.
This is more of a "SSL is a fucking black box and it has drained my will to live" config error, but blaming it on DNS is not entirely inaccurate.