This nontechnical definition of "narcissism" seems to excuse the infantilizing aspects of consumerism, assuming that definition isn't pejorative. I've criticized this aspect of consumerism in the first link below. If narcissism is somehow part of human nature, perhaps we needn't worry about First World decadence or how social media are infantilizing us? I'd expect this reassuring account of narcissism falls out of neoliberal ideology, like the happiness and self-help industries.
But I might not be understanding what you're getting at. The first video here is just distinguishing between the technical definition and the broader use of the term, the latter being equivalent to "jerk." So both of those terms would be pejorative, in which case the nontechnical one wouldn't figure into a neoliberal excuse for the consumer's infantilization. Anyway, I understand that distinction, and wrote about the technical definition of "mental disorders" in the bottom two links:
