I don't think anything necessarily "happened" to women in tech. You could just as easily say that as computer science became a more established field, men swarmed it because it was interesting to them.
Why does it matter? If we are already treating each other excellently, as I suggested, and women still won't join computing, then I don't care. If we aren't treating each other in a civil manner, then by all means that what we should do.
I'm in no way advocating special treatment for women. I want to be clear about that.
Treating people equally and civilly is a political decision. It's not happening in a lot of places, and if you really want to step in and change it, that's politics.
The points listed in the article talk about treating women in a special way.
http://apps.npr.org/dailygraphics/graphics/women-cs/child.ht...
Bear in mind that the social status of medicine, law, and STEM has (at least by my observations) remained fairly constant during that period, but that of computer science has sky-rocketed.
Do you have an explanation for the decline that doesn't call for a change in the way that women are treated in tech?