I strongly object to this idea. Getting rid of old threads is getting rid of CSTSF history. Useless threads are made throughout all eras of a forum's history, why target those from a specific time period? How can the community agree on what constitutes a useless thread? The vote would almost never be unanimous. This would also be a lot of unnecessary work with just about no payoff.
I'm assuming that your goal in this is to prevent new members from necroposting
like you recently did. Post dates are clearly visible on posts, and that warning Captain Fabulous posted appears at the top of all threads that haven't had a post for 2 months. New members have no excuse not to notice these things, so there's not much else we can do without obnoxiously shoving warnings in people's faces at every turn.
I'm not trying to condemn you for the necropost that caused you to start this thread, we've all made mistakes here; I'm just trying to stress that this is a problem that's never going to go away. For as long as this forum remains, we will continue to get new members who bump threads unnecessarily, whereupon they hopefully learn from their mistake.