> There's a metric incentivizing "maintenance tasks" so the system is biased toward the side of closing and duplicating.
If only. Sorry to say, all of this curation effort happens purely by intrinsic motivation - a desire to see a better-curated site.
It's objectively a good thing when more questions get closed (including marking duplicates) because the overwhelming majority of what gets posted is nowhere near meeting standards, and because those standards have been carefully considered with the site's goals in mind.
Those goals just don't happen to match the goals of the overwhelming majority of people who come to ask a new question on Stack Overflow. That's because they don't understand the site's purpose. There is a tremendous amount of misinformation out there (and the site owners are at least complicit in this, because it drives traffic).
In point of fact, my reputation increased the most during a period when I barely used the site at all, because I accumulated votes on answers I'd already written. And I didn't care about any of that, because it gets you absolutely nothing past IIRC about 35000. (The last privilege - https://stackoverflow.com/help/privileges - is awarded at 25000, but past that you can get an increase in the number of flags and votes you can cast daily. It would take an unimaginable level of obsession with the site to ever run out of validly raised flags, but I have run out of closure votes on several occasions.)
When I came back, I started actually paying attention to the meta site and understanding how Stack Overflow is actually intended to work, instead of just being another random person trying to contribute expertise. And my reputation has actually levelled off and declined, mainly because I award generous bounties for existing exceptional answers, or to promote the few high-quality questions I find that need a better answer (especially, questions that I'd like to use as a duplicate target, but wouldn't provide others asking the question with a good enough answer).
> bureaucrats wrecking havoc to perfectly reasonable answers trying to rack up these points.
It's not bureaucracy and it isn't "trying to rack up points". You get two reputation points for an accepted answer, only if you don't already have at least 1000 points and only if you get two out of three users with unilateral edit privileges to agree that it's a good edit (and they, in turn, are incentivized to steal your edit - not for reputation, but because they can get it published unilaterally instead of waiting for someone else to approve). You can't even reach unilateral edit privileges this way, since you need 2000 points for that.
Among people making edits unilaterally - both to questions and answers - this is overwhelmingly motivated by good faith attempts to improve quality. "Perfectly reasonable" is not the standard. The standard is "as good as the available attention allows" (ideally, people focus on more popular content). When you post on Stack Overflow, you license the content to the community (and separately also to the site and company) and they are absolutely within their rights to make good faith edits. If you want to share "your" ideas with the world and not allow others to touch, use a blog.