The Solus Team has recently been discussing the problem of resurrecting old threads. We're testing out a plugin that will warn people if they try to replying to a post that's older than a certain time (that can be configured). We weren't terribly happy with replies to old posts either (some of which really needed new threads, because the issues were unrelated).
Our main focus right now is getting the 4.5 ISO ready for everyone. This will be something we discuss more after that is released. We certainly don't want to do more moderation than we have to, it takes time away from answering questions, providing updates and maintaining the distro itself.
We have no plans to prune old support posts, even if they are abandoned by the OP. That would be a ton of work that would add to our moderation burden. Also, there are times threads like that can be useful, if they give someone else some things to try that might help them troubleshoot a similar issue. There would be not a lot of value for a lot of work.
Right now the plugin to warn people about posting to an old thread will likely be our first line of defense. We are also considering auto-locking older threads, but haven't started those discussions in earnest yet. Whatever we decide, we'll let the community know.
