Uh, because they haven't worked themselves into a tizzy about being female, as you and your feminist friends did when you were their age.
I have always, and still do, call my female friends 'girls', and I'm well into my 50's. Not all of us bought into the feminist carp in the late 60's and into the 70's.
I am over that 50 mark too and still my friends and I still say ...going to have a girl’s day.
I agree. My identity isn't so fragile that it's going to be damaged by being called "girl" instead of "woman."
I did skim the rest of the article. She quoted one young female as saying "we're afraid to be women." I think "afraid to be grown-ups" would be more accurate.