I think the key difference- at least for the book I mentioned - is that it actually teaches to you take a genuine interest in those around you. It's not a mask or a ploy, it is making you engage positively in a way that yields genuine connections.
Example: if at the start of a conversation a personal anecdote comes to mind but you think 'no that's not what the book said, I should talk about the other person instead' I'd argue you're masking your natural persona. If your natural inclination is to raise an eyebrow but no that's not what I was taught smile instead, that's a mask. You see it often among high earning people and it's pretty transparent. Luckily you often also see people who are not at all like that everywhere and they're the ones I'll prefer having a drink with 10/10 times.
There are similar socialization rituals. When you are in karate you might be taught to bow before entering a dojo or sparring with a partner. Is that an inauthentic mask because you are conforming to the respect rituals? Or how about a military salute? These norms are part of the social lubrication that makes relationships easier to form. And the process of socializing a person is teaching them to incorporate them as authentic parts of themselves.