Anarchism

Gonzalo was a self-proclaimed Maoist, part of the reason we say ML-MZT and not MLM in English

If you want criticism of a self-proclaimed ML (and don't count Pol Pot because that claim was not even paper thin), Khrushchev is someone we all hate who has slightly more of a claim to the title, though naturally I would argue that he is a revisionist.

If you want criticism of an actual ML, we criticize Stalin and Mao all the time, but usually not on "selfish abuse of power" terms because that generally isn't what they did compared to simply being a bit reactionary or foolish (often right and left deviationism, respectively, though that is a slight stretch for the Four Pests case).

Naturally, if it is an ideology we believe in, then actions we disagree with are generally going to be outside of what we consider those principles to be.