I don't think we should defund most police agencies in the US. I absolutely think that we need to defund ICE, throw a substantial number of its current employees in jail, and build a new immigration enforcement agency from the ground up. Nobody who authorized masked raids by the secret police can be trusted to enforce the law and I do not consider any agency who employs them legitimate.
If I tried to abduct someone from my local courthouse, do you think the cops would let me get away with it? Because they've worked in lockstep with ICE as they've done exactly that. Defunding the police and defunding ICE are not two separate issues.
Cops routinely let private bounty hunters abduct people, albeit not from courthouses so often. I'm not happy about it, but I don't know if I necessarily want my local cops to be equipped to fight the Gestapo.