“I know the author tempered these with “on average”, but it has a similar effect to flat out saying all women exhibit these traits.”
The author of the memo goes to considerable pains (pages 3 and 4) to explain precisely why “on average” does not mean “all” or say anything about a specific individual. Nor does he discuss people’s abilities, but their choices. Nor does he discuss ideas of superiority. He cannot be held accountable for others’ failure to read or to understand what they are reading. In fact, Damore (a little naively) assumed that his memo would be read and understood in the same light that he took pains to make clear in it. He didn’t assume, or even envisage, the shockingly low intellectual level he would be confronted with. What does that say about a sense of superiority?
So your point is valid about bad arguments. Then you’re demonstrating how bad arguments can originate, in a lack of understanding of what the issue is.