More than that. The last Dragonborn they met was Tiber Septem and that was a little over 600 years ago.
Yeah, seems kinda pointless when you think about it.
Hmm, maybe Chris Plummer voices more than 1 greybeard?
Not likely. There really aren't that many as far as I'm aware. The ones that talk probably all have different voice actors. Christopher Plummer must only do that single character, as expensive as he is. They didn't have Sean Bean or Patrick Stewart to multiple characters for Oblivion.
Well they're Nords. I don't think cold bothers them too much. Plus they have to keep up appearances. How awkward would it be if someone visited, and they were seen walking around in footy pajamas or something?
But that's what I was saying. They barely ever get visitors to see them. Is it really worth dressing up that extravagantly every single day on the off chance that you'll get one person come to see you once every half millennia?
Spoiler Nope. A guy named Klimmek brings food supplies up to the Greybeards every few weeks when the weather permits it.
Oh, that makes sense then I guess.
Spoiler This "Klimmek" must be super devoted... or super paid.