I’m unconvinced of the model you offer here.
First, I’m not really buying that Wikipedia is unreliable, since you, I, and other people treat it as highly reliable. Yes, at any point in time any individual page might be in error or misleading, but those tend to get corrected such that I trust the average Wikipedia entry to give me a reasonable impression of the slice of reality it considers.
But even supposing you’re right and people do think Wikipedia is unreliable and that’s why it’s secretly reliable, I don’t see how that causes it to become reliable. To compare, let’s take somewhere else on the internet that isn’t try to do what newspapers are but are a mess of fights over facts—social media. No one thinks social media is reliable, yet people argue facts there.
Okay, but you might say they don’t also have to generate a shared resource. But the only thing keeping Wikipedia from being defaced constantly is an army of bots that automatically revert edits that do exactly that plus some very dedicated editors who do the same thing for the defacing and bad edits the bots don’t catch. People actually are trying to write all kinds of biased things on Wikipedia, it’s just that other people are fighting hard to not let those things stay.
I suspect something different is going on, which you are pointing at but not quite getting to. I suspect the effects you’re seeing are because Wikipedia is not a system of record, since it depends on other sources to justify everything it contains. No new information is permitted on Wikipedia per its editing guidelines; everything requires a citation (though sometimes things remain uncited for a long time but aren’t removed). It’s more like an aggregated view on facts that live elsewhere. This is one things newspapers, for example, do: they allow creating new records of facts that can be cited by other sources. Wikipedia doesn’t do that, and because it doesn’t do that the stakes are different. No one can disagree with what’s on Wikipedia, only cite additional sources (or call sources into question) or argue that the presentation of the information is bad or confusing or misleading. That’s very differently than being able to directly argue over the facts.
I agree with you (meaning G Gorden Worley III) that Wikipedia is reliable, and I too treat it as reliable. (It’s so well-known as a reliable source that even Google uses it!) I also agree that an army of bots and humans undo any defacing that may occur, and that Wikipedia having to depend on other sources helps keep it unbiased. I also agree with the OP that Wikipedia’s status as not-super-reliable among the Powers that Be does help somewhat.
So I think that the actual secret of Wikipedia’s success is a combination of the two: Mild illegibility prevents rampant defacement, citations do the rest. If Wikipedia was both viewed as Legibly Completely Accurate and also didn’t cite anything, then it would be defaced to hell and back and rendered meaningless; but even if everyone somehow decided one day that Wikipedia was ultra-accurate and also that they had a supreme moral imperative to edit it, I still think that Wikipedia would still turn out okay as a reliable source if it made the un-cited content very obvious, e.g. if each  tag was put in size 128 Comic Sans and accompanied by an earrape siren* and even if there was just a bot that put those tags after literally everything without a citation**. (If Wikipedia is illegible, of course it’s going to be fine.)
*I think trolls might work around this by citing completely unrelated things, but this problem sounds like it could be taken care of by humans or by relatively simple NLP.
**This contravenes current Wikipedia policy, but in the worst-case scenario of Ultra-Legible Wikipedia, I think it would quickly get repealed.
One bit of nuance my original comment leaves out is how flexible the citation policy is. Yes citations are required to include content on Wikipedia if it’s not considered common knowledge, but also it’s not that hard to produce something that Wikipedia can then cite, even if it must be referenced obliquely like “some people say X is true about Y”. This is generally how Wikipedia deals with controversial topics today: cite sources expressing views in order to acknowledge the existence of disagreements and also keep disputed facts quarantined in “controversy” sections.