Apache also has a lot of dead projects that never got picked up by users. Apache should have a marker for zombie projects so people don't start using them.
Software projects have a natural lifecycle, and since we've been around for almost 30 years, there's going to be a number of projects in that state.
However, the ASF doesn't force projects into the attic while they still have a community around them. OpenOffice is an edge case - there's still a project community, primarily around templates and other end-user-centric activities. They're just not doing much with the actual software any more.
Granted, there's room to disagree as to whether 1) the ASF should force projects into the attic and 2) whether OO actually has an active community. But the Foundation's position is that this is the decision of the project, not one to be forced top-down by the Board.
When I find something interesting on github, before deciding to use it, I check the number of committers and the commit history/frequency.
Anyone can do the same for Apache projects.