I'm not sure since our version of the help center has lacks some information, but it seems like Roomba does take pending reopening votes and duplicate status into consideration, but only from the time it is first old enough to be eligible for deletion until the time it is a month old. Those factors are no longer considered after that, which is likely in consideration of the notion that we should have had enough time to edit the question or determine that it has at least some content worth keeping by then.
Do keep in mind that while some duplicates are useful for the purposes of drawing in new users and redirecting them to the original question, this does not necessarily apply to every duplicate. If two questions were written in exactly the same way it seems obvious that we should delete one of the two or merge them. You can extrapolate this principle to suggest that a closed post without value should be deleted
Also, principally, a score of zero is either supposed to represent a question that either has no distinctive value, or does as much harm as good, and hence isn't worth keeping. The system is very liberal regarding what's preserved. It seems like the system will preserve any question with a positive score or an answer, if it is more than a month old. Now I'm not saying that the question was utterly without value in its present form (I wouldn't have tried to answer it otherwise), but the bot can't read your question to know the difference, so it was just crunching the numbers.
Further complicating matters is that yes, you edited the post so that it was no longer fully a duplicate, but in doing so you changed the scope from an etymology question to a differences question. If the second half of the revised question had been posted as its own question, I think it could've stood on its own without being nominated as a duplicate. That may have have been better for the site since the old question could still serve as a redirect, and the new question could have drawn more attention to itself, and be rated freshly on its own merits rather than having its score intermingled with the old one. However, that's not really my point: My point is that the people who designed the bot probably anticipated it operating on questions that were more similar to their original form than dissimilar, so it's no surprise that making such a transformative edit might break the system, in hindsight.
What happened here seems like a freak accident, and nothing more.
Regarding the main feature of the question, perhaps I should not speak for others, but since nobody else is offering any insight regarding why it was closed, here are a couple of problems I see with the question as it stands:
The first is that it still seems like a partial duplicate. Why? Well you left the entire first half of the question completely unedited, so it still contains some overlap with the scope of the older question:
- "If it's an established slang expression, how on earth did it come about?"
- "What are its roots?"
Like I said, right now the question reads much moreso like a differences question.
The second is that the question is very, very broad. It seems like it should be broken up into two or maybe even three separate questions. One is the etymology question that it originally duplicated. The bulk of your edit seems like a differences question.
And finally this portion at the end is more like a single-word-request:
Did movie/film fans of yore ever used “matchmaking” the same way that “shipping“ is used today? If not, what was said instead?
We really aren't supposed to ask multiple questions in a post, for the purposes of indexing and keeping questions manageable. Questions which ask multiple questions were always meant to be closed as Too Broad. Also, I'm not sure if you folk noticed since we rarely ever use that closure reason, but it was changed to try and clarify its purpose.
Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question.
To be honest, I almost didn't answer the question at all, because I struggled to think of the words that might match, and I didn't want to leave a partial answer. Thankfully I remembered reading the Variety article in the past which served as a helpful reminder. People with more specialized knowledge probably shouldn't feel like they have to contribute three distinct pieces of knowledge in order for their answer to be useful. Yeah, I know that Stack Exchange does technically encourage partial answers, but sometimes I feel as if there are some very exacting standards here and a partial answer is never really ideal if we could have a complete one instead.
If a question has a narrower scope, it also helps to write shorter answers that are more readable, or at least give the matter extra thorough treatment for posts of the same length.
As you already know, reviewers will usually elect to keep a question closed if they observe even one applicable closure reason, since each user can only vote to close or reopen once.
Now personally, I don't even mind the single-word-request at the end too much because it has enough of cognizable relationship to the differences question to fit into a single narrative regarding the word's meaning. It implies that you want to know what purpose the newly clipped word uniquely serves.
However, etymology falls under an almost entirely different scope than meaning, and since we already have a etymology question, my advice would be to edit the question to remove the listed questions regarding the term's roots, so that people can submit distinct answers trying to antedate the X-Files watchers or Dengeki Pikachu readers to the earlier question. It would help to narrow the scope and avoid the impression that it is a duplicate.