If I recall correctly, mods of subreddits had the option to exclude the sub from r/popular or r/all or the front page or whatever it was. And that they'd do this to avoid a sub with specific rules about participation getting broken by people not from that subreddit just driving by because it was popular and posting something against the rules that they didn't bother to read, because when you're scrolling through a mass aggregate feed you might not check the subreddit's participation rules.

Just saw a post with tons of comments that would fly on the greater Threadiverse of Piefed/Lemmy/Kbin, but that very obviously broke the rules of that community. I did my due diligence reporting, and now it's making me wonder if we have that kind of feature. Or something that lets you see from All or Local, but that doesn't let you participate till you have read the rules, something like Reddit's no-participation np links.