I happened to revisit an old interesting question in a contentious topic that generated some argumentation in the comments. Most of these comments in the question and the answers are still left which I'm glad for since they are even more interesting to read through than the answers themselves.
However on the one answer, that happen to go against the rest of the answers while still being respectably upvoted, the comments have all being cleared without being moved to chat. While I fully agree with the notion that comments should be considered perishable I feel that this was a bit unfortunate as in a loss of interesting arguments and maybe even a bit unfair. I don't remember that the comment thread on this particular answer were in any worse shape than in the other answers but maybe I'm mistaken.
I don't want to make this meta-question about that specific question so I choose not to link to it here and hope that my description can work as a backdrop to my question:
What policies do the moderators use today? Would it be possible to apply a praxis of moving old stale comment threads to chat instead of just nuking them if a moderator feels the need to clean up?