The only one of these questions that I had anything to do with was Is it correct to use an apostrophe to indicate something that belongs to an object? I was very much in favor of keeping this question open when I first saw it (and answered it), and I voted to reopen it after editing the question to make it more EL&U-like. But after receiving the necessary votes for reopening, it was reclosed on different grounds—as a duplicate of Is using the possessive 's correct in "the car's antenna"?
This disappoints me. First, I put a fair amount of thought into improving the question (as the On Hold guidelines advise users to do) in order to overcome the fault that the users who voted to close found with the original wording. But once the question overcame that obstacle, a different criticism emerged and the question was blown away once again. That hardly seems sporting, does it?
Sporting or not, it brings up a second issue. The "car's antenna" question drew an excellent (but not documented) answer from Jon Hanna, and some okay (but not documented) answers from other contributors. In contrast, all four answers to the "Is it correct to use an apostrophe" question provide sources for the points they make—and in any case, they make some points and offer some evidence that aren't made or offered in the answers to the "car's antenna" question. Moreover, the question "Is it correct to use an apostrophe to indicate something that belongs to an object?" strikes me as being a more general question than "Is using the possessive 's correct in 'the car's antenna'?" and as being at least as search-friendly (although it would be even more so if we changed "apostrophe" to "apostrophe-s").
So which question-and-answer block has the greater utility? It seems to me that both have their pluses and minuses, and that you could make a case for either one. But I don't agree with the notion that the answers to "Is using the possessive 's correct in 'the car's antenna'?" have settled and disposed of the question for all time. If someone feels strongly that we should merge the answers for any two similar questions that have already attracted thoughtful answers before being identified as near-duplicates, then by all means merge them. But I don't see any sign that such a merger is likely to occur between the two blocks of questions and answers here. And in the meantime, what harm have we averted by closing the more recent Q&A block as a duplicate?
UPDATE: Chronology of the duplicate question
Just to be clear about how events unfolded in the short life of "Is it correct to use an apostrophe to indicate something that belongs to an object?" I offer a rough chronology of its major milestones.
November 11, 18:35: The question is posted.
November 11, 22:35: The fourth of four answers to the question is posted.
November 12[?]: The question is put on hold as general reference.
[some time between 11/12 and 11/17]: The question is revised to make it clearer and of broader interest.
November 17 [early]: phenry posts "Show Me the Reference!" on Meta.
November 17 [soon afterward]: The question is reopened.
November 17 [3 hours after phenry's Meta post goes up]: The question is closed as duplicate.
Now obviously it doesn't make a lot of sense to post an answer to a duplicate question; you really ought to post it to the original question. But in this particular case, the relevance of that truism is considerably easier to see now than it was at any time between November 11 and November 16.
I accept that every time I answer a question, I take a chance that the question might be a duplicate and that someone will eventually close the new question (and my answer with it) for that reason. It's the chance I take by choosing not to delay posting an answer until after I've waded through the EL&U archives in search of questions that either are duplicates of the new question or might be construed to be duplicates by someone with the power to close questions for that reason.
But it seems to me that there ought to be a better method of dealing with answers submitted to questions that are later closed as duplicates than simply saying "Sorry, but it's your fault for answering the wrong question. Next time, try answering the original one instead of the duplicate."