For me I think it has to be Russiagate. It’s just become a catch all for centrist libs to refuse to believe anything bad about their team, make up crazy conspiracies about anyone to their left or right, dismiss every contradiction of capitalism as “Russian interference”. It’s maddening. At least the RWNJ conspiracies like Q and the Alex Jones shit are usually pretty funny because of how ridiculous they are, russiagate doesn’t even have that going for it.
What are some other contenders?
Back around that time I argued a lot with online nerds (like the hacker ones) that the 90s and early 2000 boards were not utopia, that the content in them with the conspiracy theories and racism wouldn't unit people and mostly express their hegemonial (gramsci) viewpoints. Now after being told I was wrong for questioning people's conspiracies and the community handling of them I guess those were good testing balloons to see if Q-like psyops would work on a large enough share of permanently online people or newbies in the eternal september.
Wait what does gramsci have to do with early message boards