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 himself COULD be sophisticated, and I think he wrote somewhere that had he been in power instead of Stalin those 5 year plans wouldn't have been that much less painful, but the political movement he left behind produced some of the more simplistic narratives about socialism ever, on par with "muh human nature" shit
He did some genuinely intelligent things during the revolution. It's a shame the power struggle and his theories turned out the way it did, the movement he left behind, as you say, is incredibly annoying.