It's not that the numbers are "right" or "wrong." It's that the data shows there is nothing inherent about computer science that excludes women. So if women are not interested these days, there is something about the current state of affairs that is creating the friction. What we are doing here is rejecting the hypothesis "Women are simply, as a matter of nature, disinclined to go into computer science."
"Right" and "wrong" are judgment calls, though most people do feel that keeping women out of a field with no natural barriers to them is wrong. Regardless of your personal values, the historical data shows that whatever barriers exist are not natural.
I don't actually think women are unsuited for CS, but I must say that I don't find the argument that 'in the past more women were in CS' very compelling, because it makes the pretense that all variables have remained constant over the past 40 years.
The fact is that CS -- or what people on HN call CS -- has changed massively in 40 years. For instance, startups barely even existed 40 years ago, and they certainly weren't as hyped as they are now. Furthermore, gender roles have changed in the past 40 years, as has female college admission.
There's something ironically conservative in democrat-styled liberals' [0] harking back to the CS of yesteryear where gender equality was the norm. Societies change, as do fields of work. If I had to take a pundit's guess at the reason, I'd probably say that we have similar raw numbers of women in the field now as then, but more men have flocked to the field as it's proved itself as an excellent means of generating wealth, thus upsetting the ratio.
In all honesty, if I were to guess at the reason there aren't many women in CS, I'd say it's because women don't tend to care as much as men do about generating wealth. Warren Farrell's 'Why Men Earn More' came to similar conclusions: that men are more disposed to taking nastier, more stressful jobs if the pay will be higher. If this is indeed the case, then it would seem that the easiest way to attract women to tech would be to get everyone -- irrespective of gender -- involved in CS at a young age, and allow them to see how fun it can be. If women genuinely do choose to work in careers that they find fulfilling, then this would achieve the goal of increasing the numbers of women in tech without having to discriminate in any way, simply by getting more women to self-select into tech.
[0] I must say, from the point of view of a UK liberal, there doesn't seem to be much liberalism in the US definition of the term. It seems closer to socialism from where I'm standing, with its heaps of top-down reforms and regulations. Yes, this is irrelevant, and no I'm not willing to defend this statement, since -- as a UK citizen -- I have no dog in this race.
You're missing chc's point. The point is not that the older state of things was necessarily preferable, it's that the rate of women in CS fields is not steady state, which means that the status quo isn't by its mere existence evidence of the "natural" state of things (which would be the actual "conservative" argument).
Because 50% of humans are female. If there's a strong deviation from this in a large sample size, then there must be a correlation between being a woman and in CS. If gender didn't matter, there wouldn't be a correlation.
I don't deny the correlation. I question the assumption that it is due to prejudice. It could be due to differences in the predispositions to excel at different types of work between the sexes. Men and women are different.
Why are so many professional basket ball players black? Racism?
There is an implicit assumption in this and its validity is assumed. It is not being questioned.