Humans are a very flawed species. Having a more developed brain seems to also develop the ability to suppress their empathy and “enjoy”, to the point of addiction, the brain chemicals that create the thrill for violence.

Not everybody is thrilled by violence but it certainly is a common “mental illness”.

Can we fix it? Probably not without some sort of extinction event that somehow causes the people with this “illness” to be eliminated so they don’t pass it on genetically. But that may not be possible because being “violent” may be a trait that helps them survive and the more empathetic people get eliminated.