The police are not perfect. We need to hold them accountable to some reasonable standards of behavior. But if you defund them entirely, then what do you expect is going to happen? Peace and harmony?
No, what's going to happen is that criminals will still be criminals, and perhaps bolder and more blatant criminals. Drug addicts will continue to be drug addicts, and will do crazy things while they're high, and crazy things in order to get money to get high. Such people will continue to interact with non-criminal non-addict people, who will feel threatened. But now the police won't be there. Now what?
In a country with an armed population, the police probably reduce the number of misbehaving people who are killed, because (for all their flaws) they are still less trigger-happy than a frightened gun-owner who feels threatened by an encounter with some strange-acting person.