At the risk of diving into flame war territory - he argued that tech lacking women was primarily a pipeline problem. He thought you might be able to address this by giving young girls opportunities in tech that appealed to the big five personality traits more common in women, as most were more appealing to young men according to him. He never mentioned that women were less capable, just less likely to be interested. They'll never pull a quote from his essay because there isn't one that supports that conclusion.