Having more diverse editors will lead to more diverse content.
Wikipedia pages of female scientists tend to get a lot more scrutiny than ones about male scientists [1].
There's another anecdote about moderator bias and some decent discussion on the issue overall in this thread [2].
Ultimately there are some issues Wikipedia can't solve since they are just a reflection of the rest of society in many ways.
"We can't write about this scientist and her work because no one else has written about her," is a problem that Wikipedia can't solve by themselves.
[1] https://www.chemistryworld.com/news/female-scientists-pages-...
[2] https://old.reddit.com/r/TwoXChromosomes/comments/ekv3te/fem...
Can you elaborate what content you'd expect to see more of if the editors were "more diverse"? This gets thrown around a lot here, but nobody actually says what exactly they mean. There are more than six million articles on the English Wikipedia.
What would change, which topics would get more, which would get less attention if Wikipedia editors were swapped out to represent their attributed groups (along some axes; most likely gender and broad ethnicity, I'm guessing, but not social status or education) of the American society at large?
If there were more Norweigan editors then I'd expect to see more content about things that are "notable" within Norweigan history and culture.
Replace Norweigan with African American, female, etc. and you'll see how having more diverse editors would lead to more diverse content.
Like what though? Here's [1] the Portal on Norway, there are hundreds of articles on Norway and Norwegian culture. From what I can see, the Norwegian Wikipedia does not cover Norway that much more, even though you can reasonably expect that it's primarily authored by Norwegians.
There are fewer but still hundreds of pages about e.g. Zimbabwe, its history, culture, politics, demographics etc.
I fail to see what's being not presented there. I understand the concern that it may be too USA-centered, and to a small degree it probably is, but I don't believe it's anywhere near the proportions it's made out to be, and I don't believe that it would significantly shift, because it's absolutely not a special interest community that covers only their ideas. And given that the US is the lone super power right now, militarily, culturally and economically, it is to be expected that it is very well covered, even in other language versions. It's somewhat important to everyone on earth how the US works. It's less important how Liechtenstein or Lesotho are organized, and either has their own history, but their history isn't strongly intertwined with recent world history.
The super vast majority are articles that are global (in any and all meanings) in nature, explaining scientific concepts and history. You may argue that, since Wikipedia's goal is to represent the common consensus of scientists that these topics would be different if e.g. Zimbabwe had been the world's super power for the last 70 years, and I partially agree, but far from completely. We'd see a lot more information about Zimbabwean wild life, nature and environment, but we'd still see articles on lasers, genetics, space travel, the history of Arabic numerals, because there's really no reason to believe that Zimbabwean scientists wouldn't have looked into these things etc.