Perhaps police aren't charged criminally when they should be, but that doesn't seem to be because of qualified immunity.
Suing over murder is not a great recourse, anyway. You still lost your loved one, and the individual you sue probably can't pay you much.
But qualified immunity prevents those who care to take recourse from acting to take recourse. That's the issue. The police virtually never bring criminal charges against their own.
> and the individual you sue probably can't pay you much
I'm sure the police department can. They sure can afford military-grade gear.