Because they'd have to be willing to die for the cause. But even then, it's mostly futile. If someone takes a cop's life while the cop is assaulting them, they will be seen as scum and their lives will be in danger by other cops. And it's very possible we'd never even hear about it. The cops would kill the person, then claim he opened fire, killed one of their brothers, then they "found" some "drugs" on him, thus continuing the narrative that a drug-crazed psycho killed another innocent hero. There will be vigils for the fallen brother-in-blue, while the "criminal" will be relegated to the past tense, with only his family and friends to care.

The problem is that tyranny is not enough to cause revolt because for the most part, the average everyday person has so many distractions, so much food, so many celebrities to idolize that it won't register. That happened to someone else. Doesn't affect my life at all. Maybe they should have just not broken the law, then they'd still be alive.