Her initial expectation is that, with her inside understanding of female thinking, she will have an easy time courting. But she finds that in person, many women perceive and are uncomfortable with her lack of masculinity. Relationships usually fail quickly once they reach the point of in-person contact.
But there's a major exception to this rule: she also found that women usually required an extended period of online correspondence before agreeing to meet face-to-face. And during this period, her initial expectation was completely correct -- women appeared to judge the man according to how much they liked his writing, and what they were looking for was feminine, not masculine, writing. She experienced unusual success in getting to the first date in the first place.
We can make a small interpretive leap to say that this suggests women are actually looking for the wrong things when they use online dating apps, proactively selecting men they are unlikely to be attracted to in person.
Self-Made Man: One Woman's Year Disguised as a Man ( https://www.amazon.com/dp/0143038702/ ) has quite a few interesting things to say. Relevant here are the author's observations on dating: she writes that she expected to have a lot of success as a "boyfriend" with her insight into the female mind. That didn't happen -- women picked up on her lack of masculinity and in general weren't happy with it... in person.
But she did experience staggering success in the pre-first-date courtship portion of online dating, allowing her to get dates at rates much superior to what a real man would expect. Online, the women apparently didn't have a good sense of what they wanted.
Your observation reminded me of that -- people preferring a certain approach even though it's actively counterproductive.
Based on this cover, I would have thought it was a very gender neutral looking person, and probably a lot less masculine if she wasn't frowning like that. But yeah, there's a huge difference between not being masculine enough vs. not being obviously a man.