You have the cause and effect backwards.

I have had the opportunity to observe a very wide variety of businesses in several industries and have noticed the same thing as multiple studies - a high degree of sociopathy among execs. My conjecture is that this is both because aggressive sociopathy will help people rise among the ranks, and also because the structure of business will tend to actively select for those traits (unless active counter-selection is implemented).

So, sure, one does not automatically change by becoming a manager (although there are psych studies indicating high income causing reduced compassion for others), but there is good reason to expect higher "immoral or evil" behavior in higher ranks.