For the uninitiated, I believe the meme comes from Reddit, where there is one criticism subreddit, r/ThatHappened where people accuse other Redditors of making up stories of events that never actually happened, and then a meta-criticism subreddit, r/Nothingeverhapens, where people make fun of r/ThatHappened as conspiracy theorists who think everything posted online is fake. Hard to tell how much of each subreddit is trolling and how much are people earnestly criticizing each other.