When a report is market as "unhandled", is it because moderators were busy or something or is it a way to acknowledge the report is not bad but not so good as to act either?
From my perspective, reports remain unhandled because no mod decided to take any action against it based on their judgement. The report may technically not be bad (cause it would be marked as such), but it's a complicated situation and each mods chooses not to act.
AFAIK, the mods have a restricted board where they can discuss reports and in a case where a report is presented and no one can come up with a solution, it will be marked as bad.