I think there's one more, people are like Griefers except way worse.

I think usenet can speak to the problem of trolls ruinging the community. Which is why web forms came to dominate, despite usenet's superiority in technical features and access (most people had email clients before web browsers).

Usenet was ruined by a small number of people who were trying to ruin others reputations by posting all sorts of insane diatribes to the group. Plus the spammers. Uggg... the spamemrs.