I compare /r/gaming and /r/AskHistorians. The latter is overmoderated and exhibits what I call the "Reddit effect": people will take to be true and accurate anything that is said in a clear and authoritative tone. Yes much of what is on that subreddit is high-quality, but by no means is it all high-quality, and they often remove comments from people that dispute the narratives that are pushed there. The topics of history they choose to cover are very narrow and they have a pretty narrow view of what "history" is: the narrative of mainstream US academic historians.

It's a weird comparison to make, too. You're comparing a default subreddit that is mostly for memes with one of the subreddits held in highest regard. Lots of highly-moderated subreddits are just awful. Why not compare /r/AskHistorians with the large number of highly- but poorly-moderated subreddits? There are many (I won't name names) that you would expect to be reasonably neutral places but because of who picked the name originally have become politically extreme over time. Or just as a result of the effect of the upvote/downvote mechanism. The high influence that early votes have on submissions means that if a small group of people make it their life's work to watch /new (and they do exist!) they can control the narrative very successfully.

The idea that reddit mods are some great asset to the site is just strange, IMO. To me, they're one of the worst things about the website. Most of the big subreddits are dominated by the same group of power moderators who have some questionable conflicts of interests with outside forces. Smaller subreddits tend to be dominated by high-school-style cliques.