Putting confidence in a flawed system is one of the problems, and the surveillance would still be harmful even if 100% accurate, agreed. The article says "even in a world where the technology is 100% accurate, police still should not be trusted with it", giving the example of cops using the technology to identify protesters
And cops don't stop there. They also use bullshit "gunshot detection" and "predictive policing" AI which are also flawed, biased/racist and generally problematic