@coldjoint,
I expect that what will replace the police in cities will be an urban version of Shoot, Shovel, Shutup.
BLM won't like it very much, but there will be little that they can do about it. I expect that they will whine loudly though, and provide plenty of opportunity for people to mock them.
I expect that out here in the countryside, people will choose to continue being protected by a strong sheriff department.