Let me give a counter-example. PriorityQueue is a data structure implementation published as a Ruby gem in 2005: https://rubygems.org/gems/PriorityQueue/versions/0.1.2. It has not been updated since, because it doesn't need to be. It just works. (It could use better docs, but even that would be a one-time change.)
Similarly, I have a gem that helps build searches with ORMs - https://github.com/nathanl/searchlight. It doesn't directly depend on any ORM, just the "chained method calls to build queries" interface that they implement. That means I don't need to update it when ActiveRecord or Sequel or Mongoid gets a new feature. Which means I commit far less often. I consider it feature complete and only make bug fixes, which should eventually stop.
At that point, it may look abandoned, but it won't be. Just stable. Which I consider a good thing.