I wouldn’t call IRC or Email “social networks”, or even platforms at all, really. Email is more of a direct person-to-person communication platform, similar to SMS in that it isn’t really used to “publish” stuff, outside of spam (which is the worst part of email) and mailing lists (which you ostensibly have to sign up for, or else it’s spam.)
IRC is a bit more in the middle, but it’s never had much of a critical mass outside of maybe EFNet? The rest of the IRC world is too fragmented to even call it one social network. And I would say moderation problems are directly proportional to the scale of the network (EFNet has its trolls, especially in its heyday.)
Usenet has always had a huge problem with trolls... again, proportional to its usage. It was only “good” back when the internet was very young and there was such a thing as “netiquette”. See also the eternal September.
IRC is a bit more in the middle, but it’s never had much of a critical mass outside of maybe EFNet? The rest of the IRC world is too fragmented to even call it one social network. And I would say moderation problems are directly proportional to the scale of the network (EFNet has its trolls, especially in its heyday.)
Usenet has always had a huge problem with trolls... again, proportional to its usage. It was only “good” back when the internet was very young and there was such a thing as “netiquette”. See also the eternal September.