In all seriousness I feel like the common answers I saw of Diogenes (because that was like, his entire shtick) or Socrates (because they killed him for being annoying) are probably better answers but saying its Trotsky on a leftist forum is way funnier.
Trotsky is the worst even more so for the legacy he left behind. Empowering these fucking nerds to create orgs that gotcha AES countries and fall in line with the imperialist core talking points all the while claiming the banner of Socialists.
Which orgs are you referring to? There's been a few splits lol