There's no mystery here, at least as far as the article describing divorce. Children of divorced parents usually end up staying with a parent that manipulates

There's no mystery here, at least as far as the article describing divorce. Children of divorced parents usually end up staying with a parent that manipulates them into hating the parent that doesn't have custody, because there's no opportunity to tell your side of the story. It's like state-mandated propaganda, except coming from your parent. Is it any surprise then that if an authority tells you to hate something in your developmental years, that you end up hating it, and thus estranged? Also, calling it a shift is pretty disingenuous. It's more like a deliberate eradication.