Competition is not a fetish. It's not a de facto solution that showers the world with good things. Quite often it makes people do unintelligent things for silly reasons.
It's actually a mythology. And it's perfectly fine to criticise blind adherence to it.
As for women in tech - I'm always fascinated that the pressure is one way. Why don't the fashion or beauty industries - which are hardly small or financially irrelevant - complain that so few men work in them?
I suppose there's a presumption that tech is very serious and important, and fashion and beauty are trivial, silly, and vapid.
Problem is, tech is often trivial, silly, and vapid too - as is a lot of business culture. How many products have been released that fundamentally fail to work? How many projects have veered off in surreal directions because innovation[tm]? How many episodes of Dilbert have there been now?
Perhaps it's the perception of seriousness and importance that's the real problem.
As a side note, fashion contributes around £26bn to UK GDP. It's very difficult to get hard facts how software compares, because the definition can include anyone selling anything from a website. But web design and app development on their own are much, much smaller.
Otherwise, I reject this argument. I see it as mostly waving off gender concerns. "Let's not address our broken perceptions about the capabilities of women, but instead think about how we can rework the entire fabric of the industry." I'm sure everyone's going to get right on that.
I think that we already have a primarily cooperative industry culture and that stack ranking is a bad idea in general, not because of gender concerns. I disagree with your statement that this is "a deeply, irretrievably competitive industry" though perhaps we mean different things by "competitive". Seeking capital is, to a degree inherently competitive, but even early stage enraptures are more often than not willing to help each other succeed.
(Caveats: you're right that women perform in the industry just fine. Also, many women are motivated and successful in competitive environments, and those women are negatively affected by perception that their gender prevents them from being competitive.)