Hi, as we know there’s a quite good spam protection in place: new users need their posts to be approved.
Can you tell me who approves the posts? mods of the respective forums? admins?
There are also some bugs - with RSS you can peek at these unapproved posts in advance, on the other hand “active topics” lists at the top can lead you to fake 404s on these.
Judging from this, if every post that goes into the moderation queue is listed on the global “active” list, then there isn’t much spam to begin with - nothing that couldn’t be deleted after the fact.