The shitty person pushes you overboard.
Shitty people sometimes become quite pleasant as dementia progresses. Some really nice people become completely nasty. Sometimes there is no change.
I raised two special needs sons. They are okay in part because I wondered why they did things. I was curious about the first person perspective. I was interested in finding out "What's their motivation?"
So I think this is a much more complicated thing than you are making it out to be. People have a relationship to themselves. They have a relationship to their environment. They have a relationship to other specific individuals and to a larger society.
Mental health discussions often posit that you are mentally healthy if and only if you get along smoothly with other people. They often don't wonder at those other elements and they don't question the possibility that maybe it is the other people who are all messed up, not you.
I think this is a vastly complicated topic. It is both broad and deep. It touches on psychology, sociology and philosophy.
And I don't know that HN is really a suitable place to try to dig into it in a meaty way, frankly.
Who gets to decide what is a "negative" behavioral issue?
I assure you that the computer types will be among the first to be medicated to to take the edge off their "negative" behavioral issues.