Taking a bug report and making a good workitem might be a lot of work. If the same thing happens 2 years later you'd need to do the same work again if you already deleted the bug workitem. If the old stale bug ticket was still around you'd both have a) saved the work of writing it again because you would find it when searching and b) have a very good indication that the bug you are triaging might not be that serious because it has been seen before and not prioritized.

You could just automatically mark it "stale" or whatever instead of hiding it, which would give the best of both worlds. Automatic sunset for the item, without the duplicated effort.