Most of the endpoints say "deprecated" .. are we supposed use them?
Topic on Talk:Wikimedia REST API/Flow
When an end point is deprecated, "it means that it has not been useful to clients and will consequently be removed in the near future." These end points were experimental or unstable before, and have been deprecated as part of a larger clean-up effort in preparation for the 1.0 release.
So no, please do not use those end points any more. They are about to be removed in early May.