EEG studies have shown that power changes the brain, suppressing empathy and making you less capable of considering the pain of others.
The statement that "power corrupts" is will always be true, it's literally how our brains work. The powerful will always be more evil than the rest of us.
Here are some sources:
"Recent evidence has demonstrated that empathic responses are modulated by social power." "high-power people show low empathic accuracy compared to low-power people" "numerous studies have shown that people with high power are less accurate in recognizing others’ emotional expressions"
"higher socioeconomic status is associated with reduced neural responses to the pain of others" "experiments using fMRI indicates that power promotes greed ... displayed decreased response in the right and left dorsolateral prefrontal cortex, indicating a weaker restrain of self-interest when processing receiving more than others" "Power decreases empathic concern" "powerholders may experience less distress and less compassion as well as exhibit greater autonomic emotion regulation when faced with the pain of others" "elevated power impedes accurate understanding of other people’s emotional expressions" "Elevated power is associated with heightened interest in rewards while low power is associated with increased attention to the interest of others"
"In face-to-face conversations, participants disclosed experiences that had caused them suffering. As predicted, participants with a higher sense of power experienced less distress and less compassion and exhibited greater autonomic emotion regulation when confronted with another participant's suffering."