I’ve seen it fairly often by now; many people seem to enjoy posts with moderately long comment sections. I believe this is what contributes to a more wholesome experience.

Similar to how groups meet a natural breaking point when they grow too big and people cannot know each other anymore, I imagine huge comment sections create a sense of being meaningless and unheard. This discourages sensitive voices, and may appeal more to people who don’t care anyways, which isn’t exactly a great attitude for social encounters.

I can further imagine large comment sections create FOMO for the reader, and can overall be more stressful, which leads to aggression.

Just guesses and impressions. No idea if true. Also no clue how to foster that environment in a growing network.