It's because the allowance of women to exist in technical communities is already marginal due to years and years of entrenched misogyny. Women are well aware of

It's because the allowance of women to exist in technical communities is already marginal due to years and years of entrenched misogyny. Women are well aware of this which is why they often tread more carefully and avoid conflict more often than men do. One way this shakes out is that women simply remove themselves from situations like this, where they are likely to face abuse and an uphill battle for recognition. If you're already starting as a marginal member of the community or an outsider then you're going to rationally decide to avoid that conflict. You're going to find other ways to spend your time, other projects to contribute to (maybe). This isn't just hypothetical, the article itself had several examples of women who had been contributing to the linux kernel who were discouraged from doing so by the toxic environment. To break things down even simpler, whenever there is a pre-existing power imbalance it's typical for destructive actions that are, in theory, unbiased to nevertheless result in an amplification of the pre-existing power imbalance.