Each blocked site lost:
- $X directly in business missed during those hours
- The trust of users who believed the warning
If they lost these things by arson or slander, the perpetrator might be punished. But since it was the government, they'll probably get nothing but an apology.
Any justice system will have some collateral damage: standing trial costs you time, money and reputation, even in a fair trial where you're declared innocent. But since the damage is so real and sometimes severe, we should REALLY force government to be careful how it applies itself. Warrants, oversight, auditing, judicial review, etc.
No bureaucrat should have a "ruin this business" button.