Boys and girls aren't different species. I don't think you have to be a parent of either boys or girls, or indeed a parent at all, to have perfectly valid ideas on how to talk to children.
I do wonder side by side how teenagers as boys or girls differ, honestly. All of my friends and relatives with teenage girls talk about arguments, shouting and girls getting teary. I have a son who’s similar to this, but the others and what most boy parents speak of when we’re chatting is them going quiet and sad looking, or else sullen, or snapping then disappearing to the bedroom. I heard a psychologist talking about the different hormones and testosterone. So I genuinely don’t know but do honestly wonder if girl houses and boy houses are as apparently different as I have seen and heard of.
And I’m genuinely not saying she should not speak but I do think she should have mentioned that she doesn’t have boys. It’s in the same way a teacher/ care giver with children will speak about children from a different place to one who doesn’t because they know the at home stuff that goes on, the daily issues that crop up from experience.