ACAB when the definition of cops becomes "anyone who seeks to enforce standards or act in defence".

"Become ungovernable" as a slogan that occasionally gets used to justify wrecker behaviour and self-serving egotistic actions.

I guess these two are interrelated but imagine if you said something blatantly racist in a less-than principled leftist space but you strategically deployed the slogans "ACAB" against the people calling you out and used "become ungovernable" as a justification for your actions; you could easily split a movement by doing something like this.

To a lesser extent, "it is right to rebel" gets used for the same sorts of purposes. It's divorced from its cultural and historical context; China around Mao's era was very hierarchical and society was very strictly centred around "conformity" (using shorthand here, don't come at me). Under these circumstances, it was absolutely right to rebel and exhorting people to rebel was the correct course.

That doesn't mean that it's somehow a tacit endorsement of contemporary western liberal hyper-individualism though. If anything the western left needs a good dose of "Shut the fuck up and learn how to fall in line because your petty bickering and your blind adherence to knee-jerk, cultish individualism is a major roadblock to advancing the cause of socialism".