So they overcompensate by bragging and self-centeredness.
I don't like those traits either. I've had exactly two people in my life who were like that. One was the mother of my son's best friend. She annoyed me to no end. She constantly bragged about her kids. She had twins, and she referred to them (even in their presence, as "the twins"). She rarely talked about anything else.
Meanwhile, I was really big on not referring to my triplets as a group; they are individual people. My boys found out they were triplets from their 1st grade teacher. I guess it never dawned on them that they had the same birthday, etc. It was normal to them. I also didn't brag on my kids - I let people find out what was worth bragging about on their own.
I find it distasteful when mothers of young children brag about their kids and
never stop. It is one thing to be proud of your kid for something, but quite another when even their being able to breath elicits admiration for a healthy child.There are other things to talk about. I never knew it was a thing, but I think it is a waste of time for an 9 year old's class to learn pi to the 100th decimal place. Why brag about something like that? If my sons had been in that class, I would have made it clear to the teacher that I refused to let them do that assignment (unless they wanted to; which they would not).
The other was a couple who made a lot of money, who always talked about what they bought and how much it cost, and what they were planning to buy and how much it cost. I finally had to not be friends with them. Before they made a lot of money, they were not like that. It was tedious and didn't resemble anything like their great conversations with me in years past.
But, and this is a big but -- I do not have a problem with being kind to people. It takes hardly any effort, and it may brighten someone's day. I do not view it as being responsible for how they feel about themselves. There cannot be enough kindness in this world! One never knows how people are really feeling on the inside or what problems they are carrying, unless they are close friends, usually. They still deserve kindness, IMO. Even if they were a bragging, boring, conversationalist. Even if they refer to their kids as "the twins".