I don't think those demanding defunding of police know what defund the police means. Defunding means to reduce their funding.

My point is that the police are essential, and that defunding them would make the country more dangerous.

ACAB means All Cops Are Bastards, and is not a "fringe" group but a slogan used for decades to insult the cops. It's been hijacked by the BLM movement as slogan to express their hatred for cops. I appreciate you're not on Twitter, but if you were you'd realise that it's not "fringe".