I might be giving 4chan too much credit but I think in your analogy it’s more akin to 80’s punk (broad subculture) than slam dancing (specific cultural phenomenon).

The way I see it, I lost interest in 4chan because I grew up and became an adult, and so did most of the Internet. We can look back and appreciate our childhood overall while also cringing at the embarrassing parts. 4chan has a lot of both good and bad memories for me and I think the broader Internet as well.