There are some very specific kinds of interactions that are much harder to find anywhere else. At the same time, large subreddits tend to have stringent rules, which mods frequently apply in an inconsistent and subjective manner.
I get that it's hard to manage a sub with thousands of people, but at the same time, it is frustrating to make an effort to write a long post just to realize there is no place for it.
To make matters worse, the principle of charity is basically unheard of, and people will evaluate your sentences in such a way to make them the least true, sometimes adding personal hostilities.
Posting on Reddit feels like something that should require a legal department, and I would very much like to stop doing that altogether. At the same time, places like /r/emacs are essential to help me quickly solve issues, and /r/destructiveReaders/ gave me some of the best criticism of my material I have ever had (and I'm including people from outside the Internet).
So I guess it comes up to self-control to not waste my time with subs that are prone to be toxic. But it's hard, sometimes.
Do you still post on Reddit? If so, what are your strategies to avoid unnecessary frustration?