The protestors/rioters broadly seem to assume if they demand stuff vigorously enough then it'll happen. What's the premise? That people are just being bad on purpose. That they could do better and refuse and just need to be pressured.
The protestors/rioters are broadly ignorant of how hard it is to run a police department or government better. They have no idea how to do better and haven't really thought about it. They assume that good policies are easy to come by and the issue are motivation, bias, tribalism, etc., not facts, logic, paperwork, etc.
They are looking at this as a social issue about a clash between different social groups each pursuing own agenda (the agenda is thought of as greed and self-interest for their opponents, but disinterested altruism and kindness for themselves). They aren't looking at it as problems of logistics, scheduling, budget management, writing good training curriculums, communicating better with the public about what laws and policies make sense, and so on.
They think the reason things aren't better is the people with high social status and power don't care about the people with low social status. So they just have to circumvent regular social climbing by forming a mob and exerting strong pressure to get their demands heard. They just have to be pushy so they can't be snubbed anymore.
They have no idea that organizing a society is hard to do as well as we're currently doing it, let alone better. They are contributing ~nothing to rational reforms and aren't trying to and have no idea that better ideas are needed. They aren't trying to read books like Bureaucracy. They aren't trying to study statistics to better understand crime rates and their correlations to e.g. race or income. They aren't trying to consider downsides of proposed new policing policies and how to figure out new policies that will actually work without breaking a bunch of stuff that works now. They don't understand the difficulties police face and don't care to. And they certainly aren't studying unions as a major force that blocks reforms.
It's hard to do great but we could do somewhat better pretty easily if so many of the protestors themselves, and their (partials) fans/allies, would stop voting in bad people over and over. They have no idea what the sources of problems actually are, nor which of the problems they see in the world are real (some are!) or imaginary (some are this too!). They just blame capitalism and racism.