No. The Dark Triad describes personality traits within the psychological norm (subclinical level). High scores may indicate a "challenging" personality, a tendency toward dominance, or pragmatism, but they do not make a person a criminal or socially dangerous.
Clinical psychopathy is a severe personality disorder. Psychopathy as a Dark Triad trait manifests in everyday life as low emotional responsiveness, risk-taking, impulsivity, and a lack of fear regarding social disapproval.
In certain situations, yes. Individuals with moderately expressed Triad traits often become successful leaders or crisis managers due to their stress resistance, ability to make tough decisions quickly, and strategic thinking.