If anything, the RM should have a couple of built-in features, such as:
1. A warning flag mentioning that the add-on is not current--in other words, does not work with the newest version of XF;
2. A warning flag if the resource is over a certain age (admin selectable, such as six months, one year, etc.);
3. A way for users to report outdated resources as "dead" or "unsupported" where hopefully the site admin can flag these resources as such, or move them to a "graveyard" so forum members realize the resource is inactive;
4. A rating system similar to WordPress where downloaders can report whether the add-on "works" or not; it would be separate from the overall star ratings.
My frustrations with WordPress and its many thousands of abandoned and/or outdated plugins and themes is starting to manifest itself here as the number of add-ons grows. And I would think that any site offering their own "resources" will likely see the same. Some sort of flagging system would really help keep things current.