That's the clinical condition and no one is arguing that it's not a tough row to hoe. It doesn't compare to normal narcissism.

But experts estimate that only .5-5% of the US population are clinical Narcissists. It's not prevalent.

Generalised narcissism was already embedded in the language since 8AD before psychologists came along and made it a clinical condition though. Some people are weaponizing it but more seem to understand the difference and use it appropriately. Some experts say that it causes defensiveness. It might in the moment, but so does pointing out someone's being selfish or self absorbed. But those two are easier to disregard and ignore. If someone tells you you're becoming a narcissist though, that's not so easy to dismiss. It sticks. Seems like you'd be more likely to self reflect before things really got bad.