Unless the accountability can be applied with a high degree of consistency (i.e. never IMO), then such accountability has no value to changing this mindset.
There are systemic interventions, but the bottom line is the only way this changes is if the relationship between the public and the police is built on mutual interests. It's really a shame that "defund the police" became the slogan, because if instead it were "support the police" e.g. reallocation of resources to make their jobs easier and clearer, maybe some minds would have been open instead of rammed further shut.
There is no de facto obligation for the police to care for the public beyond not stirring an uproar despite sedating words like "protect and serve the community". They exist to protect the state(reputation and finances of the state) and the common people become a concern only after the state is not harmed. Utilizing new sedative words does not change the matter. Mutual interest needs to be defined and implemented into protocol, and not just via manuals or "rulebooks" but in actual practice.
Police proper are usually formed under the power of the local executive branch. Not that the sheriff system of being elected or not creates its own perverse incentives to engage in misconduct, but police departments are created to reduce the amount of public monitoring that can be done. Usually, the local executive is not voted out simply because of police misconduct/corruption, in part due to lack of information; other matters also matter more to voters.
Through both education and experience, officers eventually learn very well, in part from the criminals they deal with and the lawyers in the legal system, the means of conducting misconduct and getting away with it.
Defunding the police indeed is an ineffective slogan. Often the cuts cause the amount of cops deployed to be reduced, which means those still employed can engage in misconduct. Taking away the money does not do much. Social workers have their own set of biases and ways of screwing over people, just nonviolently.