"the study" lmfao.
This is getting more and more absurd.
Look, a well-written villain is liked, not empathized, because people recognize them as a chaotic force of nature and that is formidable in its own perverted way. Nothing wrong with it. Examples of amazing psychopaths:
Hannibal Lecter, Negan (TWD), Patrick Bateman.
Many people love these characters despite being pure evil, because they have charisma, and because they are GOOD at their jobs and people admire being badass and "pro". Also, they have their twisted set of principles and morality and people love rules, even the wrong ones.
The case of Negan is one of the strongest for this argument, since he is introduced to the audience in the most disgusting way possible, and later on, thanks to those "admirable" traits, he gains their respect.
A study that dismisses such obvious things is immature and lacks any serious insight.