I have never once gotten sound advice off of anything I’ve read on Reddit. But I also don’t use Reddit. I Google search if I can’t find what I need on Wowhead.
WoW forums have not been helpful in the last few years. Lots of trolling and meaningless threads. I only just started posting a little here and there but often find myself responding to a thread, then end up discarding the response because the topic have been derailed.
about 13 years ago i frequented a WoW forum over at DSLreports, which got past the work network’s content filter for “gaming”. it was never a busy subforum, and these days i use that site for ping and speed tests
There are all kinds of subforums in this very forum with people that help others. There’s CS, for players to help other players, UI and Macros where players adept in those help others, etc. Take a look around.