"Reframe the job of police and provide adequate resources in the other broken areas of society so that untrained police aren't the first ones to the scene of a mental health crisis, who are a bit trigger happy because they were trained that everyone is out to kill them, or even better, provide adequate community investment and resources such that ideally both crime and mental health doesn't reach the point of crisis which requires police officers, at least less of the time if we are being realistic here" isn't as catchy of a slogan. You can't exactly chant that during a protest.

Could it have been said better? Sure. But more than half the country actively rejects any attempts at nuance, thinking that if you can't stop ALL school shootings, or have a vaccine that is 100% effective at preventing infections, that it isn't worth doing at all. It's hard to get people on board with your nuance when they only acknowledge binary thinking.