I checked Their repository, and its last release was about 3 years ago, with only three 1/2 years old issues still open. And Wikipedia also confirms that.
Is this project still actively maintained or developed? Does anyone use it or recommend using it?
Well, there are two interpretations to your question.
Literal: is Calligra unmaintained? Clearly not.
Spirit of the question: Can non-developer get a more recent release than three years ago? Apparently not and the release part is clearly neglected somewhat.