Clearly police officers are above the law in America. Clearly blue lives matter/thin blue line is a very deep cultural problem within the force. Clearly police unions protect people who shouldn't be protected. Clearly police officers protect their peers when their peers commit crime. Clearly there is some level of infiltration by white supremacists into police forces. Clearly police in major cities do not do a very good job of de-escalation at all.
The average citizen has almost certainly seen a video of a police officer acting outrageously and not ending up in prison. Everyone here has theories that will solve it: end qualified immunity, fix incentives, destroy police unions. Most likely none of us are experts. I can't shake the feeling that there is some truth or barrier to this problem that the average person doesn't know about/the government doesn't think we can handle being told.
If nothing else any reform must have the blessing of police officers. If police officers quit en masse that is something society at large isn't willing to tolerate. Just like the old slashdot e-mail reform meme of ol' (https://yro.slashdot.org/story/04/04/06/1629219/analysis-of-...), I suspect we need a similar meme for police reform.