People react, but their reaction is channeled into a false dichotomy. What the elites learned from 1984 etc. is that you do need to provide an enemy for the people, but the people are not united; so you need to provide two enemies, each of which is a champion of one side and a foe for the other, and then let the spectre of this false choice become the defining characteristic of people's identity.
Witness it in the people who hate Trump or Clinton or Biden or anyone else that is put forward: you can divide an entire country on it right down the middle, and meanwhile their policies in reality (not policy positions! implementations!) are basically indistinguishable. The same thing would happen regardless of who is elected, for the most part, because the election is a show, a pressure release valve to make people think they've done something.
Even now we have people who think that electing Biden will help solve the problems you've pointed out. People ostensibly on the Left are mad about four years of rhetoric that has been riling them up, and have pulled the lever for "change" to resolve this. And yes, you will _hear_ less about blacks being shot by police for four years - that's part of the strategy, which the media cooperates / coordinates with. The actual number of incidents may not change... Instead, it will be time for news stories and events which angry up the Right for a few years, again forcing them to direct their resources and energy at fighting some spectre that won't change anything instead of directing their efforts inward to truly root out corruption and decay.
There is no protest. Protests are just the establishment throwing a different sort of parade, celebrating their power by demonstrating what they can allow to happen without facing any consequences themselves. Go ahead, yell in the street, burn down a city - nothing changes because nobody is listening and your actions ultimately only hurt people lower down the chain.
Surveillance did not stop the summer of Antifa and BLM rioting. It will not stop a summer of redneck riots if that's in the cards either. Surveillance probably does stop people who actually stand some chance of causing real change; but if that is a functional, working thing, you won't hear a word about it.