I think that was clear...my point is that by doing so, the moderators would be removing content that someone building their vehicle may find valuable. Sellers will also refer to older listings to help set a price. As a buyer, if you are digging through listings, I'd suggest paying attention to the date the listing was posted. If a listing is old enough to be removed by a moderator, it's a safe bet that it's not still available...so the reason for removing is only to save a buyer from looking at the posting date (which displays right under the post title)
Ok this will be my last response on this thread. I see value leaving the threads up to view for sure. Perhaps disabling people from responding to old ads would be helpful? Just suggestions to keep things clean is all. Have a good day.