“Defunding” doesn’t really mean a complete elimination of the police, but a radical reworking of its role and the amount of funding it gets.
The reasons given against this are reminiscent of the reasons empires give against accepting the independence of the colonies: that the savages won’t be able to manage themselves and achieve peace on their own.
Even if that were true, and it’s not, the system as it is—a systemic oppression against minorities—is untenable and inexcusable.
Defund the police. Redefine the role it plays and allocate resources away from violent repression and towards helping the growth of the community.