[rspeer]

That doesn't really contradict what duaneb said.

Most of these are the largest subs because new users are subscribed to them by default. Default subs are just faceless crowds that don't have much of a community. You're defining "value" in terms of the aggregated number of eyeballs looking at ads, which I suppose is one measure, but the value of a site to a user is what it shows to them. They get this value from the subs that they choose to subscribe to.

For example, the sub that was directly affected was IAmA, a default sub which in its current celebrity-focused incarnation is no more a community than the audience of The Tonight Show is a community.

[ObviousScience]

But what about things like /r/askscience, which most people agree provides high value content?

That they're also unhappy and have the same list of complaints strongly suggests that reddit isn't doing a good job supporting their communities.

[duaneb]

Look at /r/askhistorians, which is probably one of the highest quality subreddits on the site. They moderate the subreddits tightly and decline being a default subreddit. With effective mods the friction with Reddit goes away. It is easy for me to see that community mods are terrible, especially on the default or topic subreddits.

/r/askscience is comparatively poor quality. Wrong answers are often given with no repercussion. Answerers are often entirely unqualified to answer question. This is arguably worse than no answer at all. I would not consider it a quality subreddit.

What you see on reddit is: people blowing gossip out of proportion on the subreddits who allow it. Those that "went dark" are probably the reasonable ones to avoid to avoid poor content.