I wonder how to handle duplicate, late answers from new users? Today I reviewed this late answer which is almost an exact duplicate of this answer. The reason these late answers are reviewed from my understanding is to prevent new users from adding low quality answers. In my opinion a duplicate (actually a sixlicate because there are six 'duplicate' like answers) answer to a 1.5 year old post validates as being low quality and unwanted.
So I doubted a bit what to do since there is no flag for 'duplicate answers' and looked up this answer on Meta.
The only times I'd seriously consider flagging is when the duplicate is posted days or weeks after the original.
After giving it a bit of thought I chose to flag the answer, after all I'm reviewing this late answers to sort out the hidden gems between the junk. But the flag got declined because:
flags should only be used to make moderators aware of content that requires their intervention
In my opinion the moderators intervention should have been deleting the post, after all we want users to post useful answers, but it seems I'm wrong.
So my question is: When I'm reviewing late answers from new users and they give a duplicate answer, what should I do with it? I'm new to the whole Stack Overflow reviewing and if I do so I like to do it right.