Community bumped an old question that most likely won't ever have an accepted answer. Should something happen to questions like these or is their occasional churn just part of keeping the site alive?
As you put it, their occasional churn is just part of keeping the site alive.
My understanding is that questions are good, a high answer count is better, accepted answers are best. One way or another, all of it counts towards pushing this community out of beta. The thing to do with them is if anyone sees an abandoned to just treat it like any other question by answering it, flagging it for policy violations, or just leave it alone.
At the same time, I've seen answers accepted months after the question was asked (and I am guilty of that as well), so I really don't want us to start deleting them, which is the only other alternative here.