In my previous incarnation (SPAM ISSUES in the Site Display Problems explains) I asked this once. So far as I remember the gist of the editors’ reply was that they were happy for everything to stay on the record indefinitely. Which makes it ironic (or poetic justice) that it is my topics that were accidentally wiped from the record. So I’m putting this one back on the record.
I’d been struck by the number of “where should we go?” type of threads that people (and not just spammers) were still posting suggestions on long after the original questioners must have not just chosen their holiday but been and come back!