In some cases, sure people come to the forums because they are mad about something. I don’t know that that is in most cases.
I highly doubt that people go to the Trust Level 3 Lounge forums to post because they are mad about something. Indeed, I don’t think I’ve seen any “mad” posts in that forum.
I also don’t think that being mad is the only reason people post on these forums. If I were to make a guess using the term “most” about these forums, I would guess that most people who post on these forums care about WoW.
Do you think that this tanking guide for WoW Classic was from someone who wasn’t happy?