I think the difference is that it’s not fringe obsessives but rather everyday people spreading bad info. Stuff like QAnon, white nationalism, anti-vax, GamerGate and so on might be mostly started and kept well alive by fringe obsessives but plenty of normal people are sharing their memes, lies and content in an uncritical manner in a way that’s very different to personal websites. Social networks have made it much easier for these lies to be spread and repeated whitewashing their true origins and becoming accepted.