> I’d rather have ten duplicate questions for every question
Sure, unless it really happens. I'd been burned by over-moderation as well but when I look at the process I think it's not arbitrary. There are controls and voting by more than one person. Remember, there is nothing a moderator gains by doing any of this.
Yes, I think moderators aren't to blame for the poor quality of the experience (mostly).
But I think this recipe is a disaster: users downvote and close-vote. Moderators look at votes and clean up accordingly. I think the problem is that the algorithms allow a small group of drive-by downvoters to destroy the experience. I'd be more than willing to accept a somewhat lower content quality for a more friendly experience.
Well, what is the downside to having duplicate* questions?
I would guess the vast majority of traffic to any specific question page is search, followed by specific links people have posted (on or offsite), and relatively little will come from browsing through lists of questions (tags pages) or something like that.
Search is going to surface the most up-voted and linked questions. Links people have posted are obviously very specific (no chance of confusion following the link).
I would say the upsides are that you end up with more opportunities to have nuanced differences in question handled, give more people a chance to answer questions, naturally refresh questions/answers over the years (eg: "How do I minify CSS in <stack>?" will have very different answers in 2019 than it did in 2009).
* I'm not necessarily suggesting exact duplicates, but allowing for questions to be re-asked after a year or two, and allowing any subtle difference in the situation, stack, etc.
Sure, unless it really happens. I'd been burned by over-moderation as well but when I look at the process I think it's not arbitrary. There are controls and voting by more than one person. Remember, there is nothing a moderator gains by doing any of this.