> if people were held accountable indefinitely for the externalities caused by the work they conduct

Yes, it would change peoples priorities: If this was the case (and the definition of "externalities" was broad enough to encompass "No civil discourse, no cooperation; misinformation, mistruth") literally nothing of consequence would ever happen.

The those tropes in computer engineering about suits never getting fired for buying IBM, about legal departments wrapping everything in red tape, about bosses insisting on processes, reports and cover sheets? They are on the hook for vague 'externalities', so they cover their asses. Only when we collectively accept a certain degree of risk can progress happen.

Running for the nearest torch and pitchfork shed is not how an open, liberal society deals with adversity.