I agree with your last paragraph, but also there are a number of cultural factors that might be in play with this sort of thing.

E.g., in many cultures parents will disparage their children in a humble-brag sort of way, like "oh, you're lucky your children are so well-behaved! Joannie is so difficult to deal with, I try to get her to do her chores but all she wants to do is study calculus!" as a way of expressing "Joannie is really studious and therefore better than your children, nyah nyah."

Natch, I have no particular reason to believe that was the case with the people you're describing here.