It's selection bias because it's a hot topic. There are articles in between those to posts and I don't believe she posted the article to HN. It's just a selection of her blog that the HN userbase likes. I don't particularly agree with her POV but I think it's unfair to characterize her blog as about the gender gap.
As an aside, it's not like men are actively encouraged to become programmers by their social peers. There are a small group of men who program and support each other in that vein, in the general population it doesn't exactly represent the hopes and dreams of parents of male children. (Eg. Mom and Dad statistically would encourage becoming a lawyer or doctor much more than a programmer).
I think as a society we should encourage women and men to do what they want rather than that they should fill some predefined gap that we think needs filling. I could care less about the gender gap in computing or the gender gap in nursing.