But since we lack an individually actionable way of making the police better, doesn't the argument reduce to "we should not help the police as they are now"?
My previous post was responding to your claim "But an argument that no-one should help the police is basically an argument the police shouldn't exist", which is incorrect. The two are very different arguments.
I take "not helping" to mean not just not developing specialized products that only police can legally use, but also not calling the police in case of crime, not helping them with investigations as witnesses. Where the law permits, not selling them generic products and services (eg food). And where personal circumstances permit, not working for a company that does business with them, deplatforming them, etc.