The original laws of this country did not permit lawsuits against government employees acting in an official capacity. After the Civil War, the Civil Right Act of 1871 was passed allowing citizens and residents to sue government officials for civil rights violations suffered under color of law. The qualified immunity doctrine was created by the courts after that to shield public officials from nuisance suits for discretionary actions (generally meaning bureaucratic actions) by people angry over actions that went against them (i.e., for denials of licenses, judgments, etc.).
Unfortunately, due to the volume of nuisance suits, this doctrine got stronger and stronger over time. At some point, the courts began applying this strengthened doctrine intended for bureaucratic actions to police actions.
I realize that a huge number of people completely disagree with that, and I don't really know how to persuade any of them other than to urge them to examine history and note the consequences of authoritarianism.
Put another way, if your local DMV agent is acting funny, you can still sue the DMV, even if you can't sue the agent directly, FWIU
Anyway, hopefully the SC will throw this all out in the coming weeks.