Cranks come in all shapes and sizes. There is a shit ton of generic anti-imperialist cranks for instance. But the know it all thing and contrarianism are basically engrained into trotskyism as an ideology though. Trotskyism is very popular in the west because of anticommunist propaganda, people like the idea of communism but find it easier to say "that wasn't real socialism and here is why" rather than try to deprogram anticommunist thought. Also, anticommunist bullshit instilled in westerners minds is a major roadblock to upholding Marxism-Leninism in general.

I will concede that while the pamphlet/newspaper thing is actually a good thing that gets made fun of a lot.