Haven't read the article.., but it makes sense..
Low-self-esteem --> more vulnerable to being affected emotionally by other people's actions/opinions --> more strongly affected by such actions/opinions --> more emotional damage (anger, humiliation, depression, sadness, etc) --> wanting to make it go away --> seeking revenge to make the other person feel the same way and bring that person's emotional well-being down on a relative level
Think about it.., the drama queen ugly girl from high school who would die inside trying to get back at every person who make her feel miserable inside or said something bad about her.., trying to insult them.., ruin their lives.., etc.., and then look at Kid Rock or George Clooney.., honestly.., if someone says something about them.., who gives a sh*t.., they know who they are.., the other person is just feeling insecure and jealous.., it's almost insulting for these people to insult back.. which is why you don't really see it happen..
When it happens between celebs.., they've just displayed low value for themselves.., being affected and bothered by other people's opinions of them.., like these people matter.., which is why it's funny to see Rossie & Trump go at it.., makes you wonder if Rossie is really just that crazy.., or how secure Trump really is about himself..
It might also explain why guys don't hold onto grudges nearly as long (or at all) as girls do.. Interesting article.., PM it to me if you ever happen to come across it again..
Best,
GrkScorp