Social Fad. People have experimented with hair removal for centuries. Arms/legs/more/less are all social fads. I have seen an uptick in office visits for embarrassing dermatitis or skin infections since it began. Less permanent than piercing or tatoos, I think its benign. It would be nice if our teens could understand there is more to their worthiness than their adornments.
Not routinely. I see no reason why shave her "area" for no reason. It confers no benefit whatsoever. Shaving may, in fact, cause discomfort, bleeding, infection and unpleasant ichy feeling.