Even if people don't move much, they might leave the community, or remain in the community but stop checking LW so that they look like they've left.
But it's not just about whether or not it does stay accurate, it's also about whether people perceive it to be accurate. If someone expects it to be out of date, they might not even bother trying. I (and I think a bunch of other people) find it somewhat aversive to contact a complete stranger with a request, even if that person has said it's totally okay to contact them with those requests, and it gets worse if they said it six months ago and might have retracted the offer.
(Related, if I did contact someone and got no reply, I would then find it somewhat aversive to contact you and let you know about it. I might also forget to do that, it's difficult to trigger off of not getting a reply to an email. And then I'd have to wonder if you're still active...)
Incidentally, I looked for a previous iteration so we could see empirically whether or not it's still accurate, but I can't find it. LW uses the word "map" a lot. I did find a couchsurfing group that no longer seems to exist.
Regardless of how true what you're saying is, it all sounds like very weak reasons not to try. Some people find aversive to contact an stranger? Whatever, some don't. I'm sure there'll be plenty of people who won't hesitate in seizing an opportunity to meet a fellow LWer, especially if they live in less developed places where meeting interesting people is really hard.
A monthly mail confirmation sounds like more trouble than it's worth, and people might be put off by the spammy nature of it. I think fixing the map as people report problems is a better appro...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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