He was removed, not because he was bad, but because he was bad and unnecessary.

If the monster world went into a blackout, he’d have been out and operating the child-reactor with full government support. Only because Sully found a new, compatible, source of power was the ethics of the old system finally up for debate. Slavery is only allowed to be abolished after it stops being “necessary” for the economics of the system.

And yeah, it’s a movie, so he got taken away in cuffs before the new power source was operationalized, but that’s just a bit of movie magic 😉