Guilt is just as powerful, but its influence is positive, while shame's is destructive. Shame erodes our courage and fuels disengagement.
Kids who have an understanding of how and why their feelings are what they are are much more likely to talk to us about what's happening, and they have better skills to work it out.
I hesitate to use a pathologizing label, but underneath the so-called narcissistic personality is definitely shame and the paralyzing fear of being ordinary.
One of the things I did when I discovered this huge importance of being vulnerable is very happily moved away from the shame research, because that's such a downer, and people hate that topic. It's not that vulnerability is the upside, but it's better than shame, I guess.