There are 18 Vanagons on FB Marketplace within driving distance of me.
Twelve of them are air-cooled. Overall, the air-cooled Vanagons are in
nicer shape, at least body-wise, than their later-model counterparts.

Why would this be? Is it simply that they were off the road for so long
because of their reliability, or are there just more people around who can
work on an air-cooled VW van?

Jim