That's fair if they're obscure, and if there are extra mods (or at least an attempt to get some). Like, I wanted to start c/plantarfascitis, and yeah, that would be dead.

However, some of the communities I took over, I took them over because there was only 1 mod, who had never even posted to that community, and they weren't obscure topics (debian, redhat and Fedora actually)... And, the mod had never even posted

fedora and debian has so much happening constantly, it shouldn't be dead for months.. And I feel that if the mod hasn't used them in 2 years, maybe its time to pass it on