No, that statement is not true. There is no scientific evidence to support the claim that 80% of people with blonde hair and blue eyes are psychopaths or that any specific physical trait is directly linked to psychopathy.
Psychopathy is a complex psychological construct characterized by traits such as lack of empathy, manipulativeness, and a tendency to engage in antisocial behavior. It is not determined by physical appearance but rather by a combination of genetic, environmental, and neurological factors.
It's important to avoid making sweeping generalizations or stereotypes about any group of people based on physical traits or other superficial characteristics. Psychopathy is a serious mental health condition, and it should be discussed and understood based on scientific research and evidence, not on unfounded assumptions.