It depends on the community. I've seen many where the reactions are genuine and actually serves a purpose. From what I've seen, its almost always a popular js/node project that attracts this kind if behaviour like seen in this thread (based on my own observations).
Last example is vscode's santa hat[1]. It seems that that thread is mostly empty now but I remember there was huge meme thread going on in that issue or in reddit/hn when that thing was happening.