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.
But why shouldn't all people be protected from nuisance suits over reasonable mistakes?
Probably depends on exactly where you are, but in the US the "LL" in "LLC" is "Limited Liability". (The same concept applies for a C-corp, and Europe has equivalent constructs AFAIK.)
One of the main selling points of a corporation is limited liability. If you are acting on behalf of the company you are very explicitly not "jointly" or in any other way liable for its actions. There are very specific things you have to do wrong to become individually liable; this is called "piercing the veil":
https://www.nolo.com/legal-encyclopedia/personal-liability-p...